Certainly the Connecticut River Valley area, some of the rural areas around Hadley, scattered locations off of Route 2 (Monroe, Stamford, VT come to mind) and the Berkshires as suggested. The local foods movement is in full swing around these parts, and there are state programs for supporting farmers and dairies.
You can find where operating farms are located now with this link:
Berkshire Grown - Map of Producers and Buyers (http://www.berkshiregrown.org/map.html?search=farm - broken link)
If you would like to see a successful operation, drive to Shaftsbury Vermont and visit Clear Brook Farm:
Berkshire Fine Arts
There are two farms around here that sell shares in the spring (about $400) and one has a waiting list. The farmer's markets around here are fairly popular, though some of the sellers are amateurs, a few supplement their offerings with wholesale bought goods, and a few are honest to goodness organic farmers with great offerings. We need more of the latter.