The Writings of George Washington from the Original Manuscript Sources - Full text of the thirty-seven volume set edited by John C. Fitzpatrick. Over 17,000 letters and documents. Part of the Washington Resources at the University of Virginia Library. - http://etext.virginia.edu/washington/fitzpatrick/
The Diaries of George Washington - Full text from the American Memory project at the Library of Congress. - http://memory.loc.gov/ammem/gwhtml/gwintro.html
The Papers of George Washington - "Established in 1969 ... to publish a complete edition of Washington's correspondence". A selection of annotated transcripts are available online together with a number of scholarly articles. - http://www.virginia.edu/gwpapers/
George Washington's Farewell Address - Published in the Independent Chronicle September 26, 1796. JPG images of the newspaper and full HTML text. - http://www.earlyamerica.com/earlyamerica/milestones/farewell/
USA: Index on George Washington - Thorough list of Washington's speeches and papers. "Washington's Farewell" remains (as do most of the revolutionaries' speeches and writings), an integral part of American Literature. - http://odur.let.rug.nl/~usa/P/gw1/gw1.htm