These databases have mostly Spanish language material.
Search for primary source documents on history, culture, peoples, and societies of Latin American and the Caribbean. Documents include original manuscripts, signed letters, expedition records, reports, maps, diaries, descriptions of voyages, and ephemera. (Gale)
These databases have mostly English language articles, but you can restrict your search to Spanish language sources if you want.
Search for journal articles on most topics. This multi-disciplinary database is a good place to start if you don't know where else to begin. (EBSCO)