How can I find out what this song was called? it was on Fuse?

I was watching no.1 countdown on Fuse the other day and a song came on that was really catchy and I want to know the name of it so I can buy it. I have no idea of the name of the song or the name of the band or not even one word that they said. Is there a site that will tell me what it was on? Or did anyone watch it?? AHHH