If you can't find a converter (I've never used one but they must be out there) then you could always play the Real file and recordthe sound that comes through your sound card. Just make sure that you don't have any beeps notifying you of email etc. as that'll be recorded too.
I use a program called freerip it converts WMA/WAV to MP3 & back again its ideal for storing cd's on your pc in MP3 form or turning MP3 files into files for burning onto a CD.