In guitar hero from Xbox in any series 1, 2, 3, 4 or 5 or even world tour can you play any songs you want?

As opposed to the songs that they've given you. Say I wanted Kelly Clarkson since You've Been Gone and they didn't give it to you in the game, can I download it and put it in cos I played it with my friend's one and I didn't like any of the songs they've given us. He's got the whole set and none of them interests me and 3/4 of the songs I don't even know. Is it worth buying then if I don't like any of the songs in the whole set if you can't get the songs you want on there.