The free shipping is offered on both the three-pack of awesomeness, and the extra-special three-pack with an Artist Edition!
For new readers lookin' to dive into the collections -- or for folks hopin' to give a book or two as a gift -- this is a great way to save money. So head on over to the Sheldon Store, click the "free shipping" option, and get 'em while the gettin's good! The free shippin' ends Sunday night!