Sorry. If you not too familar with Photoshop, you can combine a bunch of layers into one layer into what is called a smart object. When you double click that smart object layer a window opens that shows a new image with all those layers. Sorta like a precomp.
Going back to the smart object layer you can make a new shape from that layer into a sphere.
Save the photoshop document and open it in AE making sure you recognize 3D objects from photoshop
Over at Planetphotoshop dot com, Corey Barker has a brand new tutorial on making 3D billiards in PS CS4 Extended that might help.