It's very easy John.
Check some of these out.
http://www.download.com/Rippers-Enco...0.html?tag=dir
You may want to convert it to an MP3 file instead of a WAV considering how much bigger wave files are. But then again it may only be a short song so you may want to keep the audio quality.
Or you could just download the song off of Limewire or Itunes.
What song are you trying to do? I may already have it here at my house and could just email it to ya.