Pat O'Brien has a DVD for $20. See the Seemore site. Best Fundamentals I've seen with a setup that is easy on your back and a grip that is left hand low without being left hand low.
Stockton's Book - Unconscious Putting.
Rotella's Books on Putting (mental)
Art of the Short Game
Edited by Mr. Desmond - 3/27/13 at 5:38pm