Is it possible to scan old photographs to include in my books?
You can scan in old photographs. Most personal scanners can scan an old photograph, and you can buy specialty scanners that will scan in negatives or slides for you. I would probably just hire somebody to do it for me, though; if you only have a few that you need scanned, it doesn't make sense to purchase equipment. If you have a lot of photographs to scan, then it's not worth my time to do it by hand and I'll probably get a better result from a commercial scanning company anyway.
I don't have specific recommendations since this isn't something I've had to do before; I know that there are quite a few companies that do it in my area and I'd probably use one of them as long as they were competitively priced just because I like to keep my money local whenever possible. To find one in your area, just search google for “scanning old photographs” and add in your city or state.