use keepvid.com to download the song off youtube, download the mp4 version and move it to itunes. most likely it will register as a movie, so go to options and change it to music video
Tubidy is a good one. But it can be quiet complicated so listen up on instructions on how to access it ( well this is for me on my mobile (( blackberry )) ) step1. get the internet up step2. go on...