go to
http://www.listen.grooveshark.com
You can listen to ANY song you want for free online, AND if you like the song you can press the download button and BAM you have it on your computer.
Its one of my favorite sites. You can listen to any song you ever want! its basically like streaming radio accept you choose what you want to listen to and when you listen to it. Go for it!

www.listen.grooveshark.com

Whats the song? just search it in grooveshark and then you can listen to it online or even download it.