Players in Barker's semiweekly game sessions published several incarnations of fanzines and other wonderful small press publications devoted to Tékumel through the mid-80s, including a Tsolyáni language book, demonology text, miniatures rules, etc. In 1983, Gamescience reprinted the original EPT and published the first volume of Swords and Glory, The Tékumel Sourcebook, a complete description of the world with no rules. Volume II was the Player's Handbook, giving the character generation, combat and magic rules (completely new mechanics, plus an 8-page character sheet). Volume III was going to be the Referee's Handbook, but Hurricane Hugo took the galleys and all remaining warehouse copies of Volume II out into the Gulf for a swim. This ended Gamescience's excursion into the world of Tékumel.
In 1993, Theater of the Mind Enterprises (TOME), better known for boardgames, published the Adventures on Tékumel series, including The Tékumel Bestiary, character generation, three solitaire adventure books (a total of 10 scenarios, I think), and Gardásiyal, the rest of the game rules.
In 2005, Guardians of Order, publishers of Big Eyes, Small Mouth, published Tékumel: The Empire of the Petal Throne. This roleplaying game is based on the Tri-Stat system of BESM. It is a complete game in one book, a first since the original EPT. There is still room for supplements, since many creatures, non-human races, Temple spells, and details for nations other than Tsolyánu were left out for space considerations.
A recent chapter in the Tékumel saga is net-publishing. Several netbooks from the Blue Room site have been made available on DriveThruRPG.com. Several language treatises, Deeds of the Ever-Glorious, a history of Engsván hla Gánga, and several other titles have been published in this manner, as well as EPT. Multiple independent games are in the works, to be published at a later date.