I'm wondering why don't they take the video down if the accompanying music was removed by the record company. There isn't a reason now to keep the video up. That's all too common these days.
To search youtube:
Click on videos at the top of the screen, then under categories on the left of the screen click on music and enter the song or band name in the search box at the top of the screen.
Edit: that is just 1 way to search, there are others....