The Writings of George Washington: 1745-1799
One of several outstanding digital collections of George Washington's papers, this site is a valuable resource for studying the Revolutionary Era. Materials include 17,500 letters and documents written by Washington, spanning the years 1749 to 1799.
Essentially the digitized version of the 39-volume collection of Washington's papers, the site offers a powerful search feature that allows users to limit searches by recipient and year. It also can be browsed by volume and document. The editors have included a 2,000-word introduction.
Not quite as complete as the Library of Congress's 60,000 letter collection, The George Washington Papers, this site is nonetheless a convenient and substantial research resource.