The Cyberian Express

 
Congressional Budget Office Reports
Current and historical data on budget and economic projections.
GAO Reports
The auditing arm of Congress watches over spending by various agencies. Some good information on the effectiveness of various programs can be found here. GAO investigates at the request of individual congressmen, however, so the coverage of government can be spotty and the reports can be biased toward the point of view of the requesting congressman.
House
Home page for the House of Representatives. Find basic information about the House operations here.
House Clerk
Home page for the House clerk, which compiles everything from roll call votes to how each member has spent his office supply funds. Unfortunately, some documents such as spending and financial disclosure statements still are not being placed on the web.You can only see them in the clerk's office.
House Roll Calls
Search here to see how your congressman voted (or didn't vote) on a piece of legislation.
House Press Gallery
Excellent one stop shopping site for a variety of House-based resources.
Library of Congress
Home for Thomas and lots of other goodies. You also can search the library collections to see what the Library has before making a trip or a request for specific information.
Senate
Home page for the U.S. Senate.Basic information on the Senate and its members here.
Senate Roll Calls
Check out how your senator voted on a specific piece of legislation.
Senate Search
Thomas
Perhaps the most useful website out there for reporters. Allows you to quickly search the Congressional Record for statements and legislation on any subject. Quick way to add sources to almost any story in a matter of seconds.