Hi x-man, (or, just to be safe) Hi x-girl,
Unfortunately, there does not seem to be one single book (or handful of books) that i could point you at to get a solid background in the physiology of running. Some are good (like Martin & Coe), but assume too much on the part of the reader; they tell you too much. ("Just the facts, ma'am. Just tell us the facts.")
So most people just skip the first half and get to the training bit. Which is a pity. I always believe that if a runner understands WHY he is doing such and such training he is more likely to do it better, more conscientiously and less likely to overdo it.
Any good physiology book will explain how the human body works (usually in more depth than you want to know), but will not ally it to how it applies to running.
I once read chunks of the Tim Noakes book, some years ago, but cannot remember the style of it to tell you if it would suit a reader new to the field. I have not read either Daniels or Pfitzinger, but have seen them being mentioned on here...
Maybe some of the others could chime in here with the titles of books they personally found useful.
Sorry I cannot be more helpful. Is there a specific question you need help with?