I also saw two cheap books by an astrophysicist that i have seen in lapidary journal talking about faceting. He made his own machine and people seem to rave about his books:
Amateur Gemstone Faceting Volume 1: The Essentials
Amateur Gemstone Faceting Volume 2: Expanding Your Horizons
Oh my God, i found it. It must be from the 1800s all black and white. Just kidding, but it is in black and white but there are all the pics and diagrams. I think if you make this and have to have someone make you the parts, you might do better buying one. This is not a simple tinker toy setup.
http://lapidaryworld.com/pdf/home_made_faceting_machine.pdf