As SBB says above, it is totally IMPOSSIBLE to get a clean midi-convertion from mp3 and wmv. Why? Well, mp3 is basically a big ol' compressed heap of chaos that removes any channel-recordings and other dynamics from a clean cd-recording ... and makes it useless.
This is also why making acapellas of crappy downloaded mp3's is utter and total shit. The center channel that vocals are usually recorded to is simply mashed togheter with left and right and every other dynamic and/or effects the track has to offer. It just doesnt give results.
But sure, as ObviousTroll said two posts above - you get software that listens to the song and guesses the notes. It might workn oa slow singliane po-song, but on everything else (and maybe even the piano) it wont work and will give shitty results.
So ... type in the notes by ear. Its MUCH simpler.