Randy, I agree with Steve and Boxford.
If you do pass your exam with borrowed reference material, you will wish you had access to it again at some (many times) time in the future. Do buy your research material, but shop around. As Steve said, Tom Henry has excellent prep material, you can also look at Mike Holt and James Stallcup.
But for an online exam go here http://www.mikeholt.com/examprep.php?id=examprepelectricalmaster
I think you have to pass the online journeymans exam before you can take masters exam.