Yes. A lot of these prototypes were documented in the 1997 book "AppleDesign: The Work of the Apple Industrial Design Group" by Kunkel and English (now out of print).
https://www.amazon.com/Appledesign-Apple-Industrial-Design-G...
Some images from the book can be found here:
http://www.99mac.se/forum/t/301501-samlarbok-i-nyskick-apple...
Esslinger also wrote his own book called "Keep It Simple: The Early Design Years of Apple".