Archived in the Avalon Project at the Yale Law School, this is a searchable collection of The Federalist Papers. (
http://www.yale.edu/lawweb/avalon/federal/fed.htm
)
From the Library of Congress, this site has a Timeline of Congressional Documents dating from 1774, preceding the Declaration of Independence to a century later in 1873. (
http://lcweb2.loc.gov/ammem/amlaw/
)