One of the first things I just had to do with my 3G iPhone was to supplement those Apple-supplied ringtones with my own. I have written, performed and recorded enough music that I wanted to use snips from my own recordings as my ringtones. This was easy on my old Moto RAZR, which accepted mp3 files as ringtones.
But for the iPhone I discovered there’s a bit more complex process that works equally well. There’s a publicized shortcut which involves taking an m4v file and changing its extension to m4r and then dropping it into iTunes where it is recognized as a ringtone and can be loaded into the iPhone.
But even though these files can be copied to an iPhone, they don’t appear properly in the list of custom ringtones.
So Apple’s recommended procedure, which does work flawlessly, is to use GarageBand to make a loop and export it from GarageBand to iTunes as a ringtone. Try it – it works great.