Is There A Way Of Getting Songs Off YouTube And Onto My IPhone?

There are some songs on YouTube that I love, but I can't buy them on ITunes. Is there a LEGAL way of getting the songs?

Legal way is to ask the uploader to send you the video. I use FreeMake videodownloader. It an just download suitable videos that can be played by apple devices! You can try it(Legal or illegal I don't know)