I work in a print shop, and we just use acrobat for it.
It doesn't let you edit within the text, but you can select it all, copy/paste and then edit in your new text file.
Depending on the quality of your original, it does make mistakes, but not too many.
I'd try the trial version and see if it lets you use this feature.
http://www.download.com/Adobe-Acroba...ml?tag=lst-0-3
and I think you need version 7 or newer