Archivo General de Indias: Directions and Information

Belize Electronic Library

Bullen Research Library, Bibliography of Caribbean Archaeology 

Catalogues of the National Library of Spain 

Index for CIRS: Full Text articles on Columbus, 1492, and the Spanish conquest of the Caribbean, a massive selection well worth the time spent perusing it. 

Leiden (Netherlands) National Museum of Ethnology: an exceptionally useful site, especially for those with interests in archaeological collections of pre-Columbian Amerindian populations of the Caribbean. This site permits searches of its database, which result in lists of artifacts, photographs of which are displayed along with brief notes. This is clearly the next best thing to going to Leiden, and is probably almost as good. 

The Library of Congress: The Hispanic World, 1492-1898 (includes Archivo General de Indias catalogue) 

National Library of France, English-language site: links to online collections of digitized books—see especially this link on the site: http://www.bnf.fr/site_bnf_eng/bibnumgb/index.htm 

UNESCO Archives Portal: Spain