Well, after rather a long period of time, I finally got back into things. I recently received a new tool. It's a convex spoke shave. The rounded bottom makes carving contours ever-so-nice. And the fact that it's a well made tool means that I can actually draw the thing along the surface and expect it to cut nice little curls of wood. I've only started on the outer contour of the guitar back, but already you can see the shape I'm going for.
I'll update this post with progress pictures.
March 17 - More definition, getting closer to the desired depth at the edge.
April 23 - It looks more like this.
April 26 - no new pictures, but the carving is still being worked on. It doesn't look much different now than it did in the April 23 entry, but the over all thickness is getting very close to my goal, which is to say 4mm. When I started, the whole laminated block weighed about four pounds. Now it weighs less than a pound.