I can only agree with Xoliul. Maybe there should be three categories: Basic (only showing basic concepts of modeling/etc), Advanced (covering more complicated and advanced techniques) and Projects (covering the process of modeling a whole rim/car or w/e).
Apart from that I dont really have any wishes concerning the content of the tutorials, Hamann rim sounds promising for the first tutorial. 
But as I already said...Xoliul pretty much hit the nail on the head.
PS: Can you already tell what payment methods will be offered?
(One idea for the future...maybe you should offer tutorials that, in order to be viewed, force members to be more active (e.g. you need to be this active/have that many posts to view this tutorial). I think thats really something that may attract more people.)
CPU Intel Core 2 Quad Q9550
Memory OCZ 8GB DDR21066
HDD Intel Postville G2 80GB
Graphics Card Nvidia GeForce 7900GT
Monitor Setup Samsung SyncMaster 245B Plus, Samsung SyncMaster 2443
OS Microsoft Windows 7 x64