Ann Arbor, Michigan, has a great Farmer's market. It is open Wednesdays and Saturdays. I go every Saturday that I'm not traveling somewhere. In the spring they have an excellent selection of plants, and through the summer all of the fresh produce you could ever hope for, most of it organic. It is pricey, but worth it, and most people are really friendly. It is one of my favourite things about living here.
Britt