I recommend a couple of books on the black death. Part of my prepardness planning comes from history. I want to know the actual - real life events and problems that people faced. By knowing my history, I'am better able to plan for the future.
Any kind of foxfire book (teaches how we did things before all of the technology), One Second After - AMAZING BOOK, will make you think a lot and rethink how you want to prep. - Patriot-reading now, but is very interesting another thinking book.
I would pick up a book on seed sowing and savings. I picked up one of the cheapest i could find, they are all about the same.
Check goodwill for a "medical surgical nursing" manual. They're the size of a phone book and could come in handy.
and for a third i would go with the books listed above. Stay away from "how to survive the end of the world as we know it" by james wesley. That was the latest book i read, all it listed was items to buy. It's basically one large shopping list.
SAS by John Wiseman as recommended earlier or 98.6 degrees
A book on basic animal husbandry or farming/gardening
finally, a classic survival fiction would be excellent, in this order (my preference) Alas, Babylon; Lucifer's Hammer; One Second After; Wolf & Iron; or Patriots (quit a bit of fighting at the end though)
All the books listed here definitely. I'd like to throw another onto the pile as well. I just finished it recently. "The Backyard Homestead" by Carleen Madigan. She does a great job of thinking outside the box on how to raise a ton of food, literally, on very small plots of land. 1/10th of an acre up to 1/2 an acre.