How do you get to the XCode Provisioning Organizer?
In Xcode, select Organizer from the Window menu, and you will get a window that give you all sorts of information about your devices and provisioning profiles. Also, there is an application called iPhone Configuration Utility (on my computer, it is in the /Applications/Utilities folder), which has pretty much the same information as the Xcode Organizer window.
You need to connect up your device, and when you click on the device in the Organizer window, you can add and remove profiles.
From the menu: Window > Organizer. Then on the left, expand Development and choose Provisioning Profiles