I took my NREMT test this past May and passed first time through. I didn't use any fancy aids or websites.
Websites can help you out, but I wouldn't put too much faith in them. I definately wouldn't pay for them.
Best advice I can give you is to relax. Study your book and ask questions of your instructor and perceptors. The NREMT test is actually designed to get you to pass.
This website and other forums is a good source of information and assistance as well.
My book website was crap. The websites that I did use were: id44.com, lessstress.com and this website.
Good luck.