The Boston Globe's website has a really neat tool for locating farmers' markets in your area. The tool allows you to search for markets by town or by the name of the market.
Remember, farmers' markets are a great way to buy locally-grown (meaning sustainable) produce that is fresh. The markets also help support local farmers because the farmers don't have to give a bunch of their profit to distributors like they would have to if they sold their goods in supermarkets. If your dinner plans call for some fruits and/or veggies, search for a market that's on your commute home and give it a try.