How do I get access to low level function libraries & pinout address maps on the pynq-z2 board

Hi Phil,
Welcome to pynq forum. I believe, you are asking about python source which running pynq on pynq-z2 board. If that’s what you want, you can check out the git repository:

and all the information about pynq-z2 board you can get from the datasheet:
the pinout: