LG VX-8000

i know that this question probably has been addressed many times, but how do i make sounds into tunes. otherwise, how do i make anything play from the outside of the phone and pressing the play button. i have send midi and mp3 selections that are under 30 seconds to my phone (yournumber@vzwpix) but every time it says that the receipt failed...also, what is push notification and how does it work.