I search in databases like Academic Search Premier (available free to NYPL library card holders) and ProQuest, but ultimately had more luck with Google Books and Google Scholar.

This quote from a book published by a respected publisher seemed pretty dead on. "During the Rios Montt presidency, the Guatemalan State (and particularly its army) committed more than 15,000 murders, was involved in over 1,000 forced disappearances, and ordered 15 executions by firing squads--the product of summary trials. As a result of such massive and open terror, which took place over a 17-month period, more than one million people were displaced in Guatemala; 90,000 of them sought refuge in neighboring countries."

Figueroa Ibarra, Carlos, "Guatemala: the Recourse of Fear," in Vigilantism and the State in Modern Latin America: Essays on Extralegal Violence edited by Martha K. Huggins. Greenwood, 1991: page 78.

Unfortunately that was an endnoted reference that I couldn't get to, so I don't know the original source of the quote.

I also found a useful article on the Latin American Working Group site, which includes a nice graph of the "numbers of killings and disappearances by month, 1979-1984." Another graph on that site puts the number of murders and disappearances combined at 12,000. Both graphs cite the American Association for the Advancement of Science as their source. Academic associations are usually pretty good bets for accurate information. Further down on the page they reference the same association saying that there were 18,000 rural victims in 1982. Due to the secrecy of such things, it's unlikely to find one accurate number, so you might want to split the difference and go with the 15,000 number from the Greenwood book. Or keep working your way through the LAWG Guatemala: Rios Montt page.

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