+"I bought a song for my iPhone and am trying to put it on my son's other-branded MP3 player."+
If you will be using your music across multiple platforms, make sure that all songs you rip or purchase are in
MP3 format. Many online music download stores, such as amazon.com, sell music in
MP3 format. MP3 is compatible with iTunes/iPod and virtually every other player, program, and phone.