Forgot to reply to this sooner, but all of the buses in Fairfax county have bike racks on the front. If you're early enough at the stop for the driver to accommodate you, you can take the 950 bus from West Falls Church Metro Station to the Herndon-Monroe Park & Ride (12530 Sunrise Valley Dr Herndon, VA 20191). It's only a 3 mile trip from there to the park, and for the last mile you'll be on the W&OD bike trail.
Put me down as a maybe. I can take the Metro most of the way there and can ride my bike to the park, but I don't know what else might come up in the near future.
Edited by CaptainSlug, 01 May 2009 - 10:42 PM.