Mixxx - The most powerful free DJ software in the world.
Song Cutter and Ringtone Maker - Free Online Ringtone Maker
VirtualDJ - Virtual DJ Software - MP3 and Video mix software for DJs
MakeOwnRingtone.com - Make your own ringtone! Follow the steps:
Traktor Pro - Flagship DJ software with four decks and a stunning range of creative features for maximum freedom in DJing.
Ringer.org - Ringer.org is a free ringtone maker to make ringtones from any song or audio file.