On the software scene things are a bit different. OCRs work best with typescript. If the job you are trying to do involves an older textbook with notes and headers printed in the margins, you can drive most OCR programs silly. I have a number of books, some mine, some old public domain textbooks, that I want to get into machine-readable form for editing and republication. So far, I have found the simplest solution to that is to pay Laura Sampson to re-key those works.
Scanners are fine, but nothing beats an intelligent human editor for getting text into a system.
Pictures and illustrations are another matter, of course. This is a reference work that anyone having to deal with Microsoft networks and their interface with other networking should have. It's complete, readable, and has a much better index than many such books have. For beginners, and as a refresher, I can recommend Dan Gookin's Digital Scanning and Photography, also Microsoft Press. There were a few tricks I didn't know and many more I had forgotten, and it starts at an intelligent but low-tech level.