State Historical Society of Missouri: Louisiana Purchase Bibliography
- Lists works available in the society's collections.
- http://www.umsystem.edu/shs/LouisianaPurchase.html

1911 Edition Encyclopedia: Louisiana Purchase
- Article from the 1911 Encyclopedia Britannica.
- http://www.1911encyclopedia.org/Louisiana_Purchase

James Madison Center
- Text of the 1803 purchase treaty negotiated by Madison as Secretary of State, a brief history, text of a Congressional resolution authorizing funds for the purchase, and 1903 speech by President Theodore Roosevelt on its significance in American history.
- http://www.jmu.edu/madison/center/

Teaching about the Louisiana Purchase
- Provides an overview of the Louisiana Purchase with tips for teaching about it to students.
- http://www.ericdigests.org/2004-1/purchase.htm

The Louisiana Purchase: A Heritage Explored
- A collection of primary sources and early published works, searchable by keyword. Accompanied by background essay and teachers' guide. A project of the Louisiana State University Libraries.
- http://www.lib.lsu.edu/special/purchase/

The Louisiana Purchase Bicentennial in Arkansas
- Bicentennial events in Arkansas, with news and calendar.
- http://www.lapurchase.org/

History Buff: Articles on Major Events: Louisiana Purchase
- Full text of news reports published in the Columbian Centinel and Massachusetts Federalist newspaper in Boston, from March 16, 1803 through November 30, 1803.
- http://www.historybuff.com/library/reflp.html

The Louisiana Purchase and the Exploration, Early History, and Building of the West
- The history of the Louisiana Territory both before and after its purchase by the United States. Text of 1903 book by Ripley Hitchcock.
- http://www.usgennet.org/usa/topic/preservation/history/louis/cover.htm

The Louisiana Purchase
- Developed as a college course project, this site covers the history of the purchase, presents primary source documents, and has a bibliography and web links.
- http://teaching.arts.usyd.edu.au/history/hsty3080/3rdYr3080/Louisiana/home.htm

Avalon Project at Yale Law School:The Louisiana Purchase, 1803
- Contains documents relating to the purchase: treaties, conventions, statutes, and messages to Congress during the period 1800-1804. Also includes Hunter Miller's notes on the 1803 treaty of purchase. From the Avalon Project web site of documents in law, h
- http://www.yale.edu/lawweb/avalon/diplomacy/france/fr1803m.htm

American Originals: Louisiana Purchase Treaty, 1803
- Scanned image of the original treaty signed with France. From the National Archives and Records Administration web site.
- http://www.archives.gov/exhibit_hall/american_originals_iv/sections/louisiana_purchase_treaty.html

Louisiana State Museum: The Cabildo: Louisiana Purchase
- Brief history of the treaty transactions in which Louisiana passed from Spanish control to French and then, twenty days later in December 1803, became part of the United States. Includes portraits of the men involved and additional history of the Cabildo
- http://lsm.crt.state.la.us/CABILDO/cab4.htm