The White House – The official site of the current presidential administration.
Official publications of United States Presidents' public writings, addresses, and remarks.
Government Printing Office (GPO) Compilation of Presidential Documents (1993- )
The American Presidency Project (UCSB) - State of the Union Addresses and Messages (1790- )
National Archives and Records Administration (NARA) - Charters of Freedom Website
United States Constitution (Library of Congress) - Texts, Commentaries, Historical Texts and Judicial Decisions