thats funny that you write this. I just got a children's book at the dump a week or so ago with the cutest pictures, thinking I could decoupage with it. Haven't done it yet though. I have decoupaged a lot. I'm not clear on what is holding you up. What do you need a pic of?
kathy

A finished project- do you cut the edges or tear? How much do you overlap? How much of the print do you really want to be able to read? How much do you want the photos to match- same book, same story, or theme? What to decopouge!??

I cut out images and arrange them on a background. But lots of people do more of a collage. They overlap and tear. Torn edges are softer, just experiment which direction as you get different results. (meaning the front or the back shows depending on how you tear) I checked my old bookmarks and they are gone :( Just play around with it until you find something pleasing to you. Sometimes, especially if I'm painting a background, it looks terribly ugly, but I keep at it and sometimes the worst beginnings have the best endings. If you are going to make multiple layers you probably should let it dry between layers.
Good luck,
kathy

Here is a link that might be useful: decoupage images