The best OCR software that I know and use myself is Fine Reader. I have FR v. 8, they are now up to v. 9 or 10. Remember though that the quality of the input scan determines the quality of the OCR results. Sometimes I have found it useful to manipulate the scans (clean them up, increase the resolution, delete garbage like the scanning person's fingers and the shadows on the sides) before feeding them to Fine Reader. One of the best clean-up programs is Scan Kromsator and it's free (
http://www.bolega.hotmail.ru/). However, it is impossibly hard to learn how to use.
Once you've done the best OCR job you can, then the hard part of manual proofreading begins. The OCR program will take you only so far.