Hey Thomas - so very impressed with how you are doing and can’t wait to see you hit your 30 day mark! A quit lit book as a reward is a brilliant idea. I am slowly reading my 1st book which i think is great for all sexes despite its title - I am reading Quit Like a Woman by Holly Whitaker. Just added the Freedom From Our Addictions by Russell Brand to my list.
I found the following link for quit lit books - hope this is helpful 
Recommendations for Quit Lit