Hi there David,
First a welcome to the world of 3D...
Pls mke sure that you post to the correct forum,... this is the area for Alias Power Animator and AliasStudio.
That said - I'd be willing to try to help except that I don't understand what you mean by "pop up book" so,...
It sounds to be like one of those children's books where you open it up and the inside pulls apart and folds up - creating a 3D book if you will.
If that is the case I'd think that a lattice or so for control and keyframe animation would be the best. Don't see how blendshapes would help the solution but there is always a great number of ways to skin a 3D cat.
Can you describe more clearly what you are trying to do?
Cheers,
MUTTOAB