Using a wave editor , you have to make your tones, turned from aaif's and saved as .caf files. After this you will use Diskaid to ssh your new waves into your phone, simply deleting the old and replacing with your newly made files. DO NOT TRY THIS IF ANY OF THIS SOUNDS FOREIGN TO YOU!! Root/system/library/audio/uisounds is the path to where these files are located and must be replaced. I have already done this on my 16gig 3g iOS 4.0.