Making ring tones
 

Is there a program that works with Ubuntu for making ring tones?

Ringtones, at least on modern phones, are just mono MP3 files that are down-encoded (usually 64 or 98 kbps). Any audio editor would be able to create these files, a good first step would probably be Audacity.

Getting them on your phone is another issue. Some phones will accept tones over Bluetooth, some need the physical cable to access internal phone storage, and some might need to receive the tone attached to an email or MMS.