I know for the initial half day of testing there is no authorized study material and everyone says you don't need to study. I know though that brushing up on math skills does make me sharper at math as with anything in life. So here is my question, does anyone know of any materials that can be used to study or brush up on skills/w-sim. It would be greatly appreciated, thanks.

They supply the study material for the w-sim. Other than that you could try doing online aptitude tests, maybe.. I guess. A lot of the testing is designed to find out what you know, not what you studied. I can say that having done the testing last year that at least half of the tests there is nothing out there to study. I enjoyed the testing. One thing you could practice is retaining information you hear. Not sure how you would practice but I found that test to be the most challenging.