(Naaaah...
) Anyways, I browsed the web and it is indeed hard to find... although I've found some links, but I don't know if they extract the audio instead of recoding/sampling/whatever.... anyways:
http://www.qwerks.com/product.asp?ProductID=6424
http://www.zealotsoft.net/index.htm
http://www.xvideoconverter.com/index.htm
I've found some more, but maybe you can redo the search with the terms I used: "wmv extract audio", "wmv rip", "wmv audio lossless" and some other things like that...
I also searched the "fileformat-sites" (like
http://www.wotsit.org/ for example) to try and find some clue weither the audio and video stream is encoded/compressed/whatever within eachother (so it would prevent ripping the audio), but found no clue either...