On my Prusa Mendel RepRap I have Wantai stepper motors. I get them off Ebay, straight from the factory. Like something out of Home Improvement, I went a little over the top and got steppers that are a tad overpowered for 3D printing. But, I love them, they barely break a sweat or heat up even after hours of printing.
This is a companion discussion topic for the original entry at http://reprage.com/post/30613309986/nema17-steppers-much-difference-between-0-9-and-1-8