A. Either get Foobar2000 or Winamp
B. Download vgmstream for whichever you chose:
http://hcs64.com/vgmstream.html(For foobar, the newest versions are at the bottom, winamp's are at the top. Don't ask me why because I really don't know.)
C. I know for sure there is a convert option in foobar2000, but if you're using Winamp you'll have to mess with the output option menu.