I just found out that ancestry.com has the database Reports of Deaths of American Citizens Abroad, 1963-1974. Ancestry.com's October Monthly Update e-mail newsletter mentioned the database. I was thrilled to find this out, because my great-uncle died in Mexico in 1974. I had been planning to contact the National Archives to get a copy of his death record, but since ancestry.com has the database I was able to get the record immediately and not have to spend extra money for it. And it turns out that there is some information in the death record that I did not have.