I ordered my first Helment today as a Christmas present for myself. Right now I am doing auto-x, but I hope to do some open track days in the future so I wanted to get a helment that would meet my current as well as future needs.
I decided on a Simpson Voyager SA-2000.
I bought my helment from Helment City.
http://www.helmetcity.com/helmets/bell.html
They offer free shipping, great discounts and an impressive return policy. I was told that if the helment didn't fit that I could return it and that they would pick up the shipping costs.
These guys are great to do business with and recomment them highly.
Roger