Found this on the net. This really ought to be put in the links section, really. This site has all 505 pages of this book scanned . It's called, "Computer Animation Primer" By David Fox and Mitchell Waite, published 1984.
This sucker has a ton of info about cgi, the companies back then, including the comapnies that worked on Tron as well, and has a section about the making of
Here's the link to the contents page.
Here's a direct link to the section about Tron.
Well, go on, lookie, lookie!