No matter one's location the first place I recommend looking is your local "cooperative extension" which partner with local universities, etc. For Virginia yours would be http://www.offices.ext.vt.edu/arlington/
Your next stop after that would be find a reputable nursery with knowledgeable staff. They should be able to further refine your plans.
For more information:
Read Sherri Osaka's tips "Take Steps toward a Poison-Free, Natural Lawn".