"America's Record-Keeper" works under the jurisdiction of the Executive Branch which encompasses many agencies. Here is where you can gain access to government records across all those agencies. Be sure to check out the information at each Presidential Library.
2. Founders Online: Not only are the papers of Ben Franklin, John Adams, Thomas Jefferson, and George Washington here (and we don't mean just official papers). There are letters, poems, and more. Better yet - there are 9 teaching guides including Franklin's satirical story of the Salem Witch Hunts, Abigail Adams "Remember the Ladies", and James Madison debates the bill of Rights.