Most of the required tools you'll already have around the house. New pop-up books are always pricey due to manufacturing costs, but, if you're willing to buy them used, you can get a bunch pretty cheaply. I bought all mine used for only a few dollars on Amazon.
1. Assorted Pop-Up Books
2. Hammer & Nails
3. string, duct tape, or anything that can hold the pages together
1. Eyelet Pliers
(The link is merely an example; I don't particularly recommend this brand or model. Actually, I recommend you don't buy this one because it broke on me halfway through the project.)