In Mexico City you can find most of the spices, as well as chick pea flour, all kinds for lentils for making dal and basmati rice, at the wonderful health food stores called Hansa.It looks like clearlydemon was right on the buzzer with Hansa. Sounds great! A search in la sección amarilla under the category of "especias y condimentos" might help you find some other likely candidates. Here, the good spice stores also sell other things like dried chillies and fruits, so if they're sold too then you might be on to something. I'm sure that there are also gourmet/gringo delis/supermarkets in DF which may well carry Indian spices (though, alas, I have no idea where they are). You might find, though, that you'll have to make up your own garam masala from scratch, but the base ingredients should be available. Oh, and you should, at least, be able to find cumin, coriander/cilantro seeds, cloves and cinnamon without much trouble in any reasonable (super)market.
There is one in Lomas de Chapultepec on Cerrada de Monte Líbano 16 (Tel. 5520-7606). Call them for the locations of their other stores. You can also try La Criolla on Julio Verne 90, Col. Polanco.
You might have more success searching for Hindú instead of Indian. I know it's not a correct term but it is used commonly for Indian cuisine.
I'm pretty sure you could find most spices in the San Juan market, in the Ernesto Pugibet street, near the Alameda Central (it's a place you should visit anyway).
There's also Hansa, a naturist products store in Euler, in the Polanco neighborhood (near Liverpool Polanco, a department store). They sell cardamom there, and maybe other spices. They have yummy sandwiches too.
You could also phone ISKON Mexico, a Hare Krishna association.
All these places are in Mexico City. I made a list in Google maps, hope it works.
posted by clearlydemon at 12:57 AM on April 9, 2008