George Washington's Farewell Address - Published in the Independent Chronicle September 26, 1796. JPG images of the newspaper and full HTML text.
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.
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.