So now I've got the project website online, with a free first chapter and Table of Contents. Yay!
The backend is done in Sinatra, and the book is written in Markdown (although it started as a Open Office project, ugh!)
I plan to release the remaining chapters as I edit & format them, which is an ongoing process in my free time. When that's done, I'll probably go for the freemium model to monetize the book — but a lot depends on the feedback I get!