Recently Richard B. Spence, Professor of History at the University of Idaho and author of well regarded espionage research works, Boris Savinkov: Renegade on the Left (East European Monographs/Columbia Univ. Press, 1991), Trust No One: The Secret World of Sidney Reilly (Feral House, 2002) and Secret Agent 666: Aleister Crowley, British Intelligence and the Occult (Feral House, 2008), has looked into the facts behind the somewhat suspect life of King Kill 33 author, James Shelby Downard.
You can read about the results of his research here:
http://forteanswest.com/lowfiguestedito ... ce0612.php
Nothing terribly revealing, but, it does appear that the man did indeed exist, and a number of names, places, and dates referenced in Downard's bizarro autobiography do seem to have checked out.
Its a good read for those interested in the puzzling narrative of James Shelby Downard's existence.