Thanks for breaking down each step in so much detail. Is there any value in going the "give the whole thing away for free" route? I have seen a few folks do this (http://gameprogrammingpatterns.com/)
Another way to give it away would be to play a long game of sorts by requiring people to sign up to the mailing list to get the free book. That way, you're still building up a list of interested people to spa--… market to when you write your follow-up books (and sell those for a profit).