I have with me sprint Sanyo 3810 mobile phone. I want to ask, does anyone know how to add ringtones on the sprint Sanyo 3810 for free, by just connecting via Bluetooth or some other way. What format does the ringtone need to be in anyway? I also tried the Bluetooth method but the phone that I am using to connect with the Sanyo 3810 does not seem to find it when searching for the phone even though it’s visible. Is there any way to do this. Any suggestions will be helpful.