I got an old, cheap copy of "The Art of Analog Layout" (Hastings), which describes these structures in detail. For the most part, the structures are fairly easy to recognize after you've seen them once or twice. But then there are the bizarre mystery circuits that require some puzzle-solving. For instance, where they combine a couple of transistors to save a bit of space.
I'd hazard a guess that the 20 to 50 year old tech described in that book hasn't changed much; anything that is novel is probably still under patent and will someday make it into a newer edition.
I mostly look at chips from the 1970s, since modern chips have features that are too small for my microscope. So I don't have any recommendations for a "modern" book.
