As I went to scan in reference letters from my previous job at Enform, I wanted the ability to capture the text content as well. Several years ago, I recall Pillsbury Winthrop investing in high priced software to enable OCR (optical character recognition) of the Firm's copier scanned documents.
I was not very confident beginning my search for free OCR options. It turns out the Microsoft Office suite has a decent OCR application called Microsoft Office Document Imaging. I've had this little gem for years and not known about it. If you don't own the Microsoft Office suite, you might try this link for other alternatives.
A Jon Galloway blog entry outlines the steps to create an OCR Word doc from an image.