I did the ipcc hack and have the usb tethering option enabled, but I'm not sure where to look for it on the Mac side. Should it be in System Preferences under Network? If not please advise otherwise. Thanks a lot.
I found another guide which says that to do it on AT&T you need to have the 3.0 SDK installed, so, that is most likely the problem. I only have the 3.0 beta OS installed on this computer, not the SDK itself.