Yale University Library has hundreds of microfilms of Dept. of State communications concerning Latin America. They include instructions to and despatches from diplomatic and consular officials, notes between Department of State and foreign diplomatic and consular representatives in the U.S., memorandums prepared by officials of the department and correspondence with officials of other government departments and with private firms and persons from 1806-1963.
Please consult the Latin American Microform Collections guide for Yale Libraries. The guide is arranged by country.