Here is an excellent video that clearly spells out the need to eat local. Following the video is a link to find a CSA in your area. This link has every CSA and farmers market which belongs to "Local Harvest" but there may be other small CSA's or markets in your area as well that are not members. Your community may have a CSA organization that has a list of more.
Eating locally for me is one of the biggest challenges I face and is is going to require a major shift in the way my life is organized. That is coming soon. I was once a member of a CSA but they only delivered produce in the summer and I wasn't fully satisfied with the produce they provided. Very little variety and not as fresh as I would have expected. But when I get settled in my new place I may give this a try again. Suggestions are always welcome.