Frito - FMF definately has different contracts for different levels of racers. I manage the rider support for both myself and my finacé and we both received FMF offers that were very different in discount levels. Like YOTRacer said - companies like Boyesen/Twin Air offer 6 levels of support to encompass all classes and levels of riders - from beginners to experts. Most all companies I have dealt with have multiple levels of support.
And about some of you saying that you can get better deals with your local shops... if you can - then that is great. But with sponsorships - if you are loyal to the companies, represent yourself and their products well, and do your best to promote their products... you will get more and more support from them as time goes on. Don't expect to get free stuff right off the bat - if you have that attitude you aren't going to go anywhere as far as rider support goes.
My best advice is to work out something with your local dealership as far as bike parts (like Yamaha parts, for example) and other merchandise - then try for support through the companies that you would like to represent (like Bell, Smith, Scott, Bridgestone, Dunlop, Works Connection, Twin Air, Uni... etc.). Sometimes your dealership can help you get this support straight from the manufacturers because the manufacturer will sell merchandise to you cheaper than they will to a dealership. Most deals (to answer a previous question in a post) can range from 35%-50% off, can include free shipping, t-shirts, hats, and stickers, can include great trackside support (like getting suspension tuning help at the races), can include discounts at other companies, and can sometimes even include free products. But don't accept any sponsorships unless you are going to seriously support the company and promote their products every chance you get.
Just my $.02 :)