One of the biggest challenges with cooking Latin American dishes in the US is that the ingredients are sometimes hard to find. Ingredients for South American recipes seem to be the most difficult ones to obtain. I do think that over the past years, it has gotten easier to find some of must-have ingredients for Latin cooking. I remember when I first moved to US (Texas) that it was nearly impossible to find achiote o annatto ā€“ I would use paprika as a substitute when my supply from Ecuador ran out -, now I can find achiote in many of main supermarket chains. However, there are still some ingredients that remain hard to find, especially if you live in a smaller city.
This is a list of some of the places, both online and actual stores, which Iā€™ve found useful for buying Latin food ingredients. Iā€™m including online stores that sell products from most Latin American countries, and for the cities where Iā€™ve lived o visited, some of the local places that have been lifesavers for me. I hope like this list of Latin food resources will be helpful to those who are looking for places to buy Latin groceries, and want to keep it as ongoing project that compiles as many online and offline options as possible. So, if you have suggestions of Latin grocery stores, both in specific cities or online, please send me a message or leave a comment. Please include the name, location/address, type of products and any other info, and Iā€™ll add it to this page.

Online Latin Food Resources:

AmigoFoods .com
Amigo Foods has a good selection of products, though mainly dry goods, with a couple of frozen items. Their site breaks out the products by country. Some of the things that they carry include canned fruits/veggies such as babacos, naranjillas, chochos. They also have Ecuadorian canned tuna and conchas negras. Their selection of products from other Latin countries is also good: they have Argentinean provoleta cheese, chicha morada from Peru, Peruvian ajies, Brazilian palm oil or aceite dende, Colombian malta and Colombian queso viajero, Spanish Cola Cao, and many others. Their shipping fees are somewhat high, so I recommend maximizing the number of items that you order to make it worthwhile.
Latinmerchant.com
This is the online store for a local Seattle Latin grocery store called El Mercado Latino (see more on their Seattle store below). The online store sells mainly non-frozen products such as yuca starch, maiz cancha, achiote, dried and canned hot peppers, guavas in syrup, panela or piloncillo, chicha de jora, and many more. I havenā€™t ordered from their online store, but have purchased products at the Seattle location many times.
EcuadorianFoodDelivery.com
I have never ordered anything from this store, I would love to and was very close to, but their shipping fees for frozen products to the West Coast are very high (it was going to be more than $50). They ship from Florida, so if you live on the East Coast, the shipping fees for frozen products are more reasonable. For non-frozen items they have a $14 flat rate shipping fee for anywhere in the US. If I lived closer to Florida I would definitely order some of the frozen products from their site. They carry an amazing selection of frozen products, including frozen fruits and prepared food items. They are one of the only places Iā€™ve seen that sells Ecuadorian Facundo brand products. If anyone else has used this site, please share your experience with us.

Update Oct.2012 : This site has just posted a message that they are closed until they re-build their site.

Amazon.com
Amazon has an international food section that features a selection of the more mainstream Latin food products like achiote paste, Inca kola, Maseca corn masa, lupini beans or chochos, dried corn husks, canned guayabas, tamarind pods, canned hominy, plantain chips, chorizo, and more. I can find most of these at my local stores, but if you live somewhere where you canā€™t even find achiote, then given Amazonā€™s overall decent shipping rates and customer service, this might be a good option.

Stores selling Latin/Hispanic groceries by Location

Austin, TX area

Fiesta
This is one of stores I missed the most when I moved to Seattle. They have everything from frozen latin foods (empanada discs, fruits, vegetables) to the flours and grains, as well as a great selection of fruits and vegetables including fresh tree tomatoes ā€“ though these do seem to be seasonal as there were times of the year that I couldnā€™t find them. They also had the best prices on limes, avoados and cilantro.

HEB/Central Market
Another store(s) that I miss from Texas. Central Market is the only store that Iā€™ve ever been able to find corvina fish. They also sometimes have tree tomatoes. Both HEB/Central Market have a good selection of Latin spices and dry goods such as canned hominy.

Chicago, IL area

El Condor
I wish this store was here in Seattle, they have so many of the Ecuadorian goodies that I grew up, including Amor cookies, Tangos, Manichos, and more. Their drinks selection includes Manzana, Tropicall, Inka Cola, Fioravanti, and even Guitig. They also have of the harder to find products such as purple corn flour, machica, plantain flour, ILE seasonings, aromatic herbs such as cedron and lemon grass. They also sell a lot of Peru Food brand products, which include mote or hominy corn, cancha corn for tostado, and more.
Address:
2349 North Milwaukee Avenue
Chicago, IL 60647

Seattle, WA area

El Mercado Latino in Pike Place Market
This was the first place I found in Seattle for Latin grocery products. I was so excited when I walked in and saw platanos, yuca starch, frozen fruit pulps, frozen empanada discs, hominy or mote corn, among many other products. Their frozen selection is decent, but not as great as some of the other Latin grocers. The selection of dry goods is very good and includes products from Colombia, Peru, Ecuador, Brazil, Argentina, Mexico, and more.
Address:
1514 Pike Place
Seattle, WA 98101

La Superior
This is one of more recent Latin grocery stores to open on the Eastside in Bellevue.They have a good selection of products from many Latin American countries. They have all the frozen products I like: frozen yuca, frozen tree tomato, as well as most of the fruit pulps: passion fruit, naranjilla or lulo, tree tomato or tamarillo, etc. They also have frozen banana leaves for tamales, frozen empanada discs, South American style corn, aji Amarillo, and more. They sell a couple of different brands of Queso Fresco, including the Froylan one from Oregon, which I love. They also have Argentinean morcilla o blood sausages. In the dried foods section they have mote or hominy corn, maiz cancha for tostado, yuca starch, corn flour, morocho style corn. Also, this store is right next to a Salvadorian restaurant called El Comal, which has great pupusas, so you can also stop by there for lunch.
Address:
900 160th Ave NE
Bellevue, WA 98008

La Tienda
La Tienda in Bellevue has a decent selection of frozen and dry products, their selection isnā€™t as good as La Superior, but itā€™s very close. La Tienda also has the Froylan queso fresco and fresh Mexican crema. They have the best selection of fresh plantains, they have a large box of nice green ones, another box with the ripe ones, some just perfectly yellow and others super ripe. La Tienda also has the best selection of spices and dried chile peppers.
Address:
1506 145th Pl Se
Bellevue, WA 98007

La Espanola
This was the first Latin product store I found on the Eastside. La Espanola sells frozen products and dry products, as well as some fresh products such as plantains and cheeses. Iā€™ve been able to find chicha, canned naranjillas, dulce de higos, Ecuadorian sardines (in the oval shapped long tins ā€“ perfect for bizcochuelo molds), dulce de guayaba, panela or piloncillo. The owner, who is from Ecuador, also mentioned that she can order frozen cuy, though I havenā€™t tried it yet.
Address:
13433 NE 20th St Ste A
Bellevue, WA 98005
Update September 2012 : Unfortunately this store is now closed, Iā€™ve been trying to find out if they moved to a new location, so if anyone knows, please tell me.

Saarā€™s Marketplace
This supermarket, located in Renton, reminds me of the Fiesta supermarkets in Texas. If youā€™re looking for great prices on limes, jalapeƱos, avocados, tomatillos, cilantro, then this store is perfect. Saarā€™s also sells Latin spices and Mexican dried chilies.
Address:
3208 NE Sunset Blvd
Renton, WA 98057

Kitanda
Kitanda is a Brazilian grocery store and bakery. They (obviously) sell many Brazilians food products, including coffee, Guarana, and more. They have freshly made cheese bread or pao de queijo.

Address:
12700 NE 124th Street Suite 2
Kirkland, WA 98034

Uwajimaya
Uwajimaya is an Asian supermarket, they have a few locations in the Seattle area, including one in Bellevue. Here you can find passion fruits, chirimoyas, carambola or star fruit, plantains, yuca or cassava, green mangoes, a good variety of spicy peppers, and more. They also sell yuca starch. Uawajimaya carries cuts of meat that you wouldnā€™t find in most grocery stores, including tripe, cow/pig feet, brains, tongue, etc. If you are looking for a pork leg to make hornado, they will either have in stock (ask them as sometimes they have them in the back) or can order it for you. Uwajimaya also has a good seafood selection that includes octopus, many varieties of oysters, and high quality fish for ceviche.
Addresses:
Seattle location
600 5th Avenue South
Seattle, WA 98104

Bellevue location
699 120th Ave NE
Bellevue, WA 98005

Renton location
501 South Grady Way
Renton, WA 98057

The Spanish TableĀ 
The Spanish Table is one of my favorite stores; obviously they have a lot of Spanish products, but also carry some South American products. I love their wine selection, in addition to great Spanish wines; they also have a nice selection of Chilean and Argentinean wines that are not the typical standard ones you find at the regular wine stores. In their deli, they also sell Spanish cheeses, chorizo, jamon Serrano and even merguez sausage. Their olive oils are also very good and you can find olive oil from South America. Another section that I love is their cookware; you can find the molds for crema catalana, paella and cazuela pans, cool glasses, and clay pots.They also have a book section that includes cookbooks, popular Latin/Spanish authors and childrenā€™s books in Spanish. In addition to their Seattle location, they also have locations in Berkeley, Santa Fe and Mill Valley. You can also purchase some product online.
Address:
1426 Western Avenue
Seattle, WA 98101

Paris Grocery
This is a sister store to the Spanish Table, and is literally located next door to it. Paris Grocery is a great source for French ingredients- ok, so not Latin, but if you love food, you will love this syore. They have good wines/cheses/cookbooks.

Samish Bay CheeseĀ 
This is a WA cheese company that makes great cheese. They have a variety of cheese that is the closest to Ecuadorian quesillo that Iā€™ve tried; itā€™s called Ladysmith and is amazing. You can find them at the Redmond and University District farmerā€™s markets. They are also at Pike Place markets on the weekends. Metropolitan Market, a local grocery store, also usually sells their cheeses. The only warning I have is that the cheese is not cheap, while in Ecuador you would pay $2-$3 per pound; here you pay close to $20, so not something to purchase everyday but definitely worth it for an occasional splurge.

Pike Place Market
I tell people that the main reason I moved to Seattle is because of Pike Place Market. I had a job interview in Seattle and after the interview I went to visit the market ā€“ I then decided that I had to find a way to move to Seattle (luckily I got the job). The Latino Market, The Spanish Table, and the Paris Grocery store are located in Pike Place Market. In addition to these places, there are several fruit/vegetable stands where you can also find plantains. During the late spring to late summer months there are additional farm stands outside that have great selection of locally grown Latin ingredients such as poblano peppers, tomatillos, fresh cilantro, and more. It also goes without saying that the seafood selection is great and if you are looking to make ceviche or any seafood dish you can probably find something delicious here. I also like the meat stores; they have very thin cuts for carne asada which work great for carne en palito. Ulliā€™s Sausage and DeLaurentis also have good chorizo (and many other yummy things).

Carniceria El Paisano
Carniceria El Paisano is a butcher located in White Center in West Seattle butcher. They sell goat meat as well as tripe, tongue and the other harder to find meats.
Address:
9629 15th Avenue Southwest
Seattle, WA 98106

U-Village QFC
This QFC will occasionally have fresh tree tomatoes or tamarillos.
Address:
2746 NE 45th St
Seattle, WA 98105

Metropolitan Market
Metropolitan Market is a local supermarket chain (open 24 hours); I would describe them as a friendlier and more local version of Whole Foods. At the location in Kirkland Iā€™ve been able to find things like plantains, passion fruits (at a very high price), tunas or prickly pears, achiote or annatto seeds. Their cheese section also features a lot of local cheeses, including the Samish Bay Ladysmith that is similar to quesillo (but you pay more than if you buy directly at the Farmerā€™s market).
Addresses:

Queen Anne location
100 Mercer Street
Seattle, WA 98109

Admiral location
2320 42nd Ave SW
Seattle, WA 98116

Sand Point location
5250 40th Ave NE
Seattle, WA 98105

Tacoma location
2420 N Proctor Street
Tacoma, WA 98406

Kirkland location
10611 NE 68th Street
Kirkland, WA 98033

Magnolia location
3830 34th Avenue West
Seattle, WA 98199