In Ubuntu 11.04, graphics settings for the driver could be found under "System Settings".
In Ubuntu 11.10, the "System Settings" menu has been scaled down considerably. Now I do not know how to access these settings.
Until you find a better option, just run
From a terminal or the run dialogue.
Edit: I'm using the old panels-based system and I just found its link sitting in a group called "Other" under Applications. No idea how that's translated in Unity but it should be in there somewhere.
In Unity, click on the Dash Home button and type "nv" in the search line. The Nvidia X Server Settings will be displayed.