I was recently in Oaxaca, Mexico. Like lots of travelers, I prepped for the trip by boning up at planeta.com, a terrific resource for orienting in the area, with high-quality practical info on food, culture, and ecology.
I see Planeta is running an e-conference on "Food, Health and Building Communities". There's a lot more going on than I could explain here, but you may want to check out the details at http://www.planeta.com/food.html
One promising part is a special Flickr page of World Food photos, at http://www.flickr.com/groups/worldfood