HUD provides an excellent resource on homelessness. This is an internet site, and the subject of homelessness can be accessed by search. On the page that is related to the topic, there are dozens of links. These are listed by topic. Many of the links provide specific information with the idea that a homeless person might be searching for information. For instance, there are topics such as "Local Homeless Assistance" and "Housing Counseling."
There are several topics that deal with specific aspects of homelessness, such as homeless vets. One jewel on this site is the link titled "Facts About Homelessness," which leads to a well-researched page by the National Coalition for the Homeless. Notably, at the top of their article "Why are People Homeless," foreclosure, poverty, and dwindling employment opportunities are the first reasons listed. Another link discusses numbers, and yet another analyzes demographics.
The HUD site provides links to government documents related to homeless. These documents may make for tedious reading, but they will contain a load of information related to the topic. The two that appear most helpful will be the "McKinney-Vento Homeless Assistance Act Re-authorized January 2002," and the "2008 Annual Homeless Assessment Report to Congress-July 2009." These two publications are worth reading because they are essentially primary.
The fact that this site is so comprehensive can be a bit of a hindrance. The sheer abundance of information available from one place is astounding, and one could get lost in the information unless there is a narrow focus. Nevertheless, it is valuable for the wealth of information that is available there, and the leads to other creditable sites it offers.