This is abit low-tech, but stick with me.
I used the Dragon voice recognition software for many years and despite having a professionally trained voice (great diction and clarity) I could never get the darn thing to give me than about 80% accuracy. There are just a lot of words it never could understand.
When I switched to the Apple platform a few months ago, a friend suggested I try a system called iDictate, and I am never going back the electronic voice recognition.
iDictate <http://www.idictate.com> are a bunch of LIVE transcriptionists who will take your audio file and return it for 1-cent per word. They can take dictation over the phone, you can send them a wav file, they will transcribe handwritten notes you fax in. Amazing.
And the best thing - they can add style and formatting. I can say "please put this heading in bold" and they will. Unusual words are no problem, I just s-p-e-l-l them out.
You get the idea. I still use the Sony digital recorder that came with Dragon, but I don't miss the voice recognition program one little bit.