Annenberg Foundation
Annenberg Learner: America's History in the Making: Contested Territories
This site highlights the westward expansion of settlers in North America and the effects this expansion had on Native Americans between the Revolutionary and Civil Wars.
Other
Conner Prairie: Road Through the Wilderness: The Making of the National Road
Information on the building of the National Road and its historical significance.
PBS
Pbs: Louisiana Purchase: April 30, 1803
This PBS site provides images of all pages of the original Louisiana Purchase, with a transcript.