I called this guy, and after I pressed his number, instead of hearing beep beep beep or something like that, I hear a song he puts on. How do I do that?

I have T-mobile Samsung t809 or something close to that. Please tell me how to install/put music on there! Thanks.

Can't help, I can say when I call someone and I get the Music, some are crap and don't want to hear, and if it is a good song, I don't want the person to answer, interrupting the song.
What I hate worse, is the one that says, "Please wait while we locate that person". Don't go through all the trouble of locating, JUST LET IT RING THROUGH. Plus they don't need to take credit for something a machine is doing.
That feature is called MOH(Music on hold)

Thanks!

Actually I just found In cellular talk, it is called a ringbck tone. Take Care

This may help:
Samsung SGH-T809 manual, download cell phone user manual | PhoneDog.com