Craigslist (Northern Virginia - apartments for rent)
http://washingtondc.craigslist.org/nva/apa/

George Mason University’s list of off-campus housing
http://liveoffcampus.com/georgemason/

DC Registry
www.dcregistry.com
Click on Classifieds and then Rental & Roommates.  Search Apartments for Rent, Condos for Rent, Roommates wanted, and Rooms for Rent.

Washington City Paper Classifieds
www.washingtoncitypaper.com
Click on Classifieds and then Housing.  Choose either Apartment for Rent or Shared Housing.

Washington Post/ Apartments.com Apartment Search
http://www.washingtonpost.com/wp-adv/classifieds/rentals/front.htm

Apartment Showcase
www.apartmentshowcase.com
Order a FREE Washington DC metropolitan area Apartment Guide and have it mailed to you (U.S. addresses only).
Search local apartments and take 360 degree tours of available apartments.

Apartment Ratings
www.apartmentratings.com
Read online reviews of various apartment complexes to see what it’s REALLY like to live there. Visit this site before you sign any lease!

Just Like Home
www.justlikehome.com

Finding a Roommate
Roommates in Fairfax, Virginia
http://location.roommates.com/virginia/fairfax.html
Great website!  Read profiles and see photos of people searching for roommates.  Easy to use.

Easy Roommate
www.easyroommate.com