Hey pal, thanks so much for writing, and for the interest in sketchbook 3, that's so appreciated! Unfortunately the books are now sold out, BUT I will be coming back to Kickstarter with my tutorials and art books in early 2019. If you want to be on the launch day mailing list, just mail "Add me, Lorenzo!" to email@example.com and you'll be one of the first to know when the next Kickstarter launches! If you've joined the mailing list in the past, you're already on it
Huge cheers, Lorenzo!