I recently donated several boxes of aviation books including "Turbine Powerplant Technology" and for some reason, two copies of "Aerodynamics For Naval Aviators" to the local library. I had them for years and hadn't looked at them. When I want to know something these days I go straight to google. There are excellent articles on just about everything under the sun including turbine engines from cartoonish to over the top technical. (some junk but its easily identifiable as such) I found a helicopter aerodynamics presentation that is outstanding. When I moved into the EC-145, I found several great articles on the Mast Moment Indicator that were much better that the flight manual presentation.
Check out this one for example:
Interactive Engine Education: GE Aviation
google a specific engine by nomenclature or any manufacturer to see this kind of great information.
Cheers, The Grump