Celebrate your Mexican American heritage this Cinco de Mayo! Here are some websites to help you find your Mexican ancestors.
Hispanic Genealogy Blog The blog doesn't get updated incredibly frequently but you can still find plenty of great links and information on the site.
HISPAGEN, Asociación de Genealogía Hispana Hispanic genealogy organization with articles and genealogy indexes.
The Genealogy of Mexico An older website but still useful with genealogies of some of the first Europeans in Mexico.
Mexico Genealogy Forum A forum to discuss Mexican genealogy with other researchers.
Also search the National Archives of Mexico and the National Archives of Spain. The Spanish Archives have passenger lists from Spain to Latin America 1500s-1700s.
Many of these sites are in Spanish but you can always translate them with Google Translate.