Did some amazon shopping this past weekend.
Was eyeing these two things for a long time, finally gave in.
The Making of Force Unleashed, and Walls Notebook.

The star wars book is full of pre-production concept work for the game, and there should be pages full of clone trooper sketches.

Walls notebook is a collection of nyc wall photos printed on sketching paper. Sort of like a mobile graffiti handbook for planning your wall attacks. And of course i will be filling it with cars. Keep an eye out.