The above book is a great book overall though it could stand a little more detail with the VB side of things. Take it if you can though because it does a great job laying out the basics of CR in VB. Crystal Reports Technical Reference is also extremely helpful and you may already have it. It's on the seagate crystal reports cd. Other than those, the best help seems to be on this site. I've searched for other books and come up with nothing time and time again. If you do find something, please be sure and post it.
Good luck,
CrystalVisualBOracle