You can get voice to text software, but not sure whether any of them use audio files as an input. Most applications are designed to convert Text to Speech, not the other way round.
A good dictation typist should be able to do it fairly quickly anyway
I tried an older version of it when it was Lernout & Hauspie. It was okay but still made a lot of mistakes. Probably a good dictation typist will win hands down.
err u could try playing it and recording it on word or something.... i wonder how a guitar solo would look in word... hell ive gotta try that sometime!!!
Phillips has it's own software (FreeSpeech), for that purpose. Don't know whether it can do it from files, but I used it a couple years ago and it was rather good. Mistakes will occur, no matter what.