The U.S. Congress can be even more frustrating to cover than executive agencies. Closed meetings are common, FOIA doesn't apply, and just getting a seat in the hearing room is sometimes an athletic challenge.
But even reporters outside the Beltway can - and should - cover Congress. Journalist Mark Twain said the republic is not safe as long as Congress is in session. Here are a few tools to help.
- Most of the legislative work in Congress is done in committees. A good set of contacts with press officers for committees legislating on your areas of interest is essential. You can find a list of Senate committee press officers, including phones, e-mails, and often cell numbers, here.  We don't have the equivalent for the House - but a phone directory of House committee offices is here. 
- You can often find news of local or national interest by looking at schedules of committee hearings - usually available at least the day before. These schedules are compiled in many places, but one free and generally accurate source for the House is this.  For the Senate, try this list. 
- Bill Tracking is fairly easy using the powerful THOMAS online system run by the Library of Congress. Start here.  Hint: it's MUCH easier once you get the bill number of the legislation you are interested in. Don't forget to look at committee reports for a wealth of information.
- Even if your editor won't spring for travel, you can see a lot on C-SPAN (check your local cable TV listings). C-SPAN is also available by webcast.  If it's not on C-SPAN, don't despair. Nowadays, many committees routinely broadcast hearings on their own live webcasts, so check the website of the committee in question.
- House Daily Press Gallery. 
- Senate Daily Press Gallery.