Xingtone Ringtone Maker

Ringtone is the first & only ringtone software for the Mac community.
Xingtone Ringtone Maker enables consumers to quickly convert and transfer
portions of an audio file from their Mac or a CD to their mobile phones
using cable-free, over-the-air transmission.

Users can download a free version here:

(http://www.download.com/Xingtone-Ringtone-Maker/3000-2267_4-10407180.html?tag=lst-0-2)