fre:ac - fre:ac is a audio converter and CD extractor designed for Microsoft Windows, Mac OS and Linux, distributed under the GNU General Public License.
Song Cutter and Ringtone Maker - Free Online Ringtone Maker
File Converter - Convert & compress everything in 2 clicks!
Audiko - Audiko Ringtones is a free to use mobile application that can help you customize your mobile phone by setting the most beautiful images your background and the most popular ringtones as your notification signals.
Converter365 - Convert all your files the easy way with converter365.com
MakeOwnRingtone.com - Make your own ringtone! Follow the steps: