You're getting a FREE ebook and you're complaining about having to stop what you're doing to read it, and asking for that FREE book to be converted into an audiobook? How about taking a few minutes to Google how to have a book read to you and thank the author and AppSumo for arranging for this book to be available to you?

It is available on Audible as an Audiobook.

You could always contact the author and find out if he can give you a coupon or something.