http://www.amazon.com/Designing-Buil...7107468&sr=1-1

this book isn't cheap...but he shows you how to build your own jig using plywood and angle iron. My suggestion would be to use it for pinning, not brazing. It's an inexpensive way to do it. The book is older, but it's actually pretty good. And he shows you how to build your own frameset with no expensive tools. I believe he does all the work with hand tools.

Also, check out this site for the pics of alot of great frame jigs...

http://www.geocities.com/smonfrey/fixtures.htm

Scroll down all the way to the bottom to Timothy Thompsons jig built out of 8020 aluminum extrusion. A great jig and would be easy to build.

Finally, you should check out the frame building forum. Lots more info about frame building and jig building than the General forum.