Let me guess, did you download it? Sometimes people put a more popular band's name as the artist header to promote their own music or the song they like because the other band is more popular.
Here's an easy way to figure it out, go into your p2p and type the song title in the little input box, then see what bands come up and perhaps decide for yourself? That's usually what I do when I'm not sure.
Edit: actually...google would be better
