Web site: www.stewart-museum.org
Canada: The Stewart Museum, Montreal.
The Stewart Museum contains an outstanding collection of maps and plans of North America, including many related to Louisiana.

Web site: www.cam.org/~ihaf
Canada: Revue d'Histoire de l'Amérique Française [French America Historical Review].
An online version of the journal can be found on this site. Few articles about Louisiana (most are Canada-oriented), but many useful bibliographic items.

Web site: http://www.cultura.mecd.es/archivos/index.html
Spain: Archivos General de Indias, Seville.
The Indies Archives contains a large number of documents relating to Luisiana. There are maps and plans, and a number of documents related to the period of Spanish rule which have been partly or wholly overlooked by French researchers. In particular, see:
Section XI, Archivo de la Capitula general de Cuba (Florida y Luisiana)
Section XVI, Mapas y planos (Florida y Luisiana)

Web site: www.bl.uk
UK: British Library, London.
The British Library has maps of North American and Louisiana, as well as plans of Mobile and New Orleans from the period of French colonialization and after. The most remarkable of these are found in the King's Collection.