Try it out at http://pixelresearchlabs.com/ringer.
Ringer 2.0 includes these new features:
Ringer allows users to choose any non-protected file from their iTunes library or any media file (MP3, AAC, MOV, MP4, M4V) and turn it into a unique ringtone. Ringer offers many advantages over other programs while remaining easy to use:
With Ringer's built-in waveform editor, precisely select the exact start and end points of a ringtone. Preview it exactly as it will sound on the iPhone. The create button will make the ringtone and automatically import it into iTunes where it will be ready to sync to any iOS device.
System Requirements: