Arguably the most rewarding way to commit to shopping local is by engaging with a local farmer through a Community Supported Agriculture (CSA) program. One online advocate for shopping and eating local, LocalHarvest.org, describes a CSA this way:
Here are the basics: a farmer offers a certain number of “shares” to the public. Typically the share consists of a box of vegetables, but other farm products may be included. Interested consumers purchase a share (aka a “membership” or a “subscription”) and in return receive a box (bag, basket) of seasonal produce each week throughout the farming season.