http://www.bikeforums.net/showthread...our-own-wheels
Pull this up and scroll down and there's a good photo of a homemade truing stand of excellent design. I have and use one almost exactly like it. The design and plans for it came out of an excellent online book about wheel building by Roger Musson: http://www.wheelpro.co.uk/wheelbuilding/book.php
The price for downloading is around $14-$15. It's the best book on wheel building I've seen. Very straight forward and instructive. The materials for the truing stand cost me under $10.