Added to above: AFAIK, the only categories are for speed. You go up in increments. 125-150 for the rookie pass (done from the rookie lane), then 150-175, 175-200, etc.
To go over 200 will take a minimum of 4 passes, but you get a new license at each level.
Step One go to SCTA-BNI.ORG and order a book. It will be a 2012, but will get you started. New books come in Feb?
It's not so much the licensing, as the safety apparel you must worry about. The safety gear is very specific and not always obvious. Licensing is simple and is only done at Bonneville. Other licensing isn't accepted.