Are there any electronic copies, in any format, audio or text, of the Tekumel books? My copies are so dogeared that even tape is failing to work. I haven't seen any of the audiobook sites selling copies, so I have wondered if there have even been any made. Does anyone know if any exist?

None of the novels have been digitized. You can still find copies of Man of Gold in used bookstores and online sellers pretty easily. Flamesong had a smaller print run and is harder to find. The more recent three books published by Zottola are pretty much only available from his retailers.

A number of the Professor's essays and other writings have been digitized, and are available for purchase through DriveThruRPG.com:
http://rpg.drivethrustuff.com/index.php ... rers_id=57

The original Empire of the Petal Throne rulebook is there, and the maps that came with it. A bunch of the Temple essays are there, though they are also incorporated into Mitlanyal. Lots of good stuff.

An indexed, text version (not just images of pages) of the Tekumel Sourcebook may be forth coming in the next year or so, but like any Tekumel publication, one shouldn't hold one's breath waiting for it.