This site provides information about what can be done to set up a good landlord/tenant relationship. (Click on the website, then click on 'Landlord/Tenant Info' on the left side of the page.)
This group is dedicated solely to ending America’s affordable housing crisis. They educate, organize and advocate to ensure decent, affordable housing within healthy neighborhoods for everyone.
If you know your rights, apartment hunting doesn't have to be a hassle. This site has information about your rights and responsibilities, budgeting, where to receive housing assistance and counseling, and more.
U.S. Department of Housing and Urban Development (HUD)
This explains what to do if your roommate does not pay rent, violates the lease, or moves out before the lease ends. It also provides information about adding a new roommate to the lease and offers a sample roommate agreement.