Motorola

Is it possible to use my own mp3 sounds as ringtones? When I try to change the ringtone for a specific contact, it takes me directly to the ringtones folder which will only allow me to download a new one from Verizon, which I assume I would have to pay for? I have my own sounds on my phone but can not figure out how to access them to set them as my contact specific ringtones. I am a newby Motorola W755 user so any advice will be appreciated.
Thank you