Unity Game Coding Using C#
by Michael L. Croswell is on the Unity Asset Store,
and can be purchased here!
I am removing the idea of volumes and putting the whole book in one asset.
That means that if you buy early you pay less and all updates will be at no cost for you.
Basically, you will have a book that keeps getting better over time!
You can find the free chapter, support material, and video(s) at the support page and the book online discussion at the forum.