http://www.flownet.com/ron/plisp.html
Complete with disk images so you can run it yourself on a real Apple or an emulator.
The last chapter is particularly interesting, as it describes the inner workings of the interpreter.
http://www.pjrc.com/store/teensy3.html
Never finished it, but if you like these kinds of challenges maybe you'd like to collaborate on it.
http://www.flownet.com/ron/plisp.html
Complete with disk images so you can run it yourself on a real Apple or an emulator.