The book is available as a PDF file from the Fitz Randolph MyFamily.com web site. I will have the administrator invite you to join. It's free and has tons of information on Fitz Randolphs. The book is found in the File Cabinet Section under the category "Books on the Fitz Randolphs."
It is a large file 20MB and that would require you have high speed internet access to download. There is also a supplementposted in the same section.
One word of warning about the book. Although much of it is acurate, I have personally found a couple of dozen mistakes and I have not done extensive research. Take it as a starting point for your own research. My copy is well marked up with additions, corrections and references.