Foods grown and purchased within 100 miles of your home help support local farmers and provide you with better vegetables and meats. Eat local whenever you can, from the local farmers market or from local farmers. Meats, poultry, eggs and more are usually available within 100 miles of your home. Eat local, eat healthy.
The current long-distance food system in industrial countries has eliminated small farmers and good flavors, and consumes large amounts of fuel for transportation. Here is a great discussion with Brian Halweil from the Worldwatch Institute about the benefits of locally grown food. Before coming to the Institute, Brian established a student-run organic farm on Stanford University campus. The farm was community-supported and sold produce to the University and local restaurants. In addition, Brian set up community-supported farms and organic farms/orchards throughout California and assisted farmers who were making the shift from chemical agriculture to organic.