Phones..hand-me-down phones...go phone..sony ericsson walkman..know anything about it or how to use it???

i got a phone from a friend and it is a go phione its the sony ericsson walkman and i can get txting and calls..but no pixing or ringtones...he said i can do alot with this phone and i know imdeed i can, radio mp3s but i dont know how..anyone have this phone?