Ubuntu 8 server - Problem with x windows

I installed Ubuntu 8 server and it seemed to go very well until I tried to get into the x windows system. I tried running startx, and it told me I needed to be logged in as root. (I tried to login using my user account peterv.) I logged in as root and ran start x and it said it couldn't find the program. I had done an apt get of xinit, and it told me to get x11-common instead. When I tried that, it said x11-common is already installed. I'm stumped. Can anyone help me out? I'm a Ubuntu novice, so I'd appreciate any help.