Back to Basics
As far as my books, a good place to start is the beginning: Volume One. It goes over the basics on program design, such as efficient training splits and effective exercise selection to develop the ideal physique. It also reviews diet and has a chapter on 7 strength training strategies for fat loss.
At 40, low to moderate volume done frequently throughout the week is best. Volume One reveals that ideal frequency. If you have issues with diet, then the diet chapter will make your food choices much simpler and clearer for you.