American Presidency Project, UCSB
Searchable database of the Papers of the Presidents back to Washington, the Weekly Compilation of Presidential Documents (Carter to G.W. Bush), and the Daily Compilation of Presidential Documents (2009-current). Also party platforms back to 1840, convention speeches, candidates' remarks, election debates back to 1960, executive orders and proclamations, presidential approval back to 1941, vetoes, state of the union addresses, press briefings.