If you want to add a free ringtone to your LG Revo then do this
1) under settings---> connectivity------> Default connection: set to mass storage. Then check "always ask"
2) Hook up your phone to your computer
3) Click open the S.D. card and open the folder _ExternalSD
4) Create a folder titled "ringtones"
5) Add any song you want.
6) Safely remove device then open office on the Revo and go into ringtones, then play a few to make sure they work. From the play menu set the songs as ringtones.
I have had issues in the past of my ringtones being dropped out as ringtone options. If this happens simply open up the music player and set some songs as ringtones.