Well if you buy it this is what you will get:
1) The RedHat installation CDs
3) Documentation Manauls
4) Some extra software CDs, that you can probably download, ex. Staroffice.
Check out their site, and they tell you exactly what you get if you buy the package:
Those two links take you to the personal and professional verions of RedHat. To the right you will find a list of what each package contains.
Bascially I think most people buy the package for the manuals, since I think the support is not unlimited. You get 30 day web based insallation support, but then again I could be wrong.