EDIT: Looks like this offer is now on hold. However, there is a coupon code of stlmommy which will give you 40% off any purchases of their books.
It seems fitting that today is International Children's Book Day because if you join their fan club, you'll get a free The Adventures of Thumbs Up Johnnie book sent to you! I've never heard of the series before, but my little brother loves it when I read a book to him at night so I'm sure we'll put this freebie to good use. Bonus points if the characters allow for me to make goofy accents and absurd ad-libs.
The fan club is located on the bottom right of the site, under the main picture. There's no confirmation link or announcement on the site that you'll get the free book, but I've talked to the author of the book and have been assured that fan club members will get the free copy.