How Did They Vote?
The U.S. Congress Votes Database provides one-stop shopping for that and much more information. According to The Washington Post's website, "This site, washingtonpost.com's U.S. Congress Votes Database, is a deep database of every vote in the United States Congress since the 102nd Congress (1991). It lets you browse votes in a variety of ways -- both in aggregate and for individual members of Congress."
For people needing or wanting to track the votes of federal legislators, this site is worth bookmarking or RSS feeding.