While I own a Nook, I do know from looking briefly in the samples that the artwork is indeed included. Though, from my personal experience with similar books, I recommend getting the physical copies. The artwork is laid out on the pages and makes the books more visually entertaining, while eBook versions downsize them and limit their size per page. Which sadly makes them less visually entertaining.

That's just my opinion. It's highly up to you. Enjoy the books. :)