Many airlines run direct flights. Are you inquiring about direct or non-stop?
I don't believe there are any non-stops to the bay area from DCA. However, if non-stop is a must, then depart from IAD to SFO or OAK. Its only a short cab ride from DC or the East Falls Church Metro (West Falls Church will cause you to back track a bit). The fares for non-stop generally cost more!
Either way Kayak.com or expedia.com are good starting points.
Last edited by DAL-767; Feb 16, 2011 at 8:22 am