Originally posted by BT
You've got to find a latino market, if necessary by driving south. This is latino soul food. Yes, Mexican markets should have them. Also, of course, Cuban, Puerto Rican and so on. I checked a few online sites such as http://www.latingrocer.com/
and, as expected, they sell bagged plantanos but not raw plantains (they'd probably get mashed in transport and the shipping cost would be prohibitive).
You could also check the on-line yellow pages for latin grocers in towns within driving distance of you, most likely down toward the Gulf coast.
And if you do order some, be careful that you get the kind you want. They are sold and eaten in all stages of ripeness but the different ripenesses are used for different recipes. For chips, you probably want them fairly ripe (yellow/black, not green).
Good luck! Where I live, it's just a matter of walking a couple blocks to a Mexican market.