Welcome to the area! I'm an hour south of D.C., so I don't have as much first-hand knowledge, but here are a few sites to check out:
www.habibihon.com
www.cleoscloset.com (see navigation links for events, teachers, etc.)
www.wameda.org
Many dancers in the D.C. area are active on Bhuz, so I'm sure they'll chime in soon.