Hello, my name is Kiichi. I'm a developer at ObjectGraph LLC. I just created this website as a joke, and I hope people enjoy with their creative humor. If you are a programmer, you must love O'Reilly books. So this website is created by an O'Reilly fan, and I wish this website contributes to O'Reilly book sales (this means, nothing evil against O'Reilly). If there is something offensive on this website, please send request/claim to info (at mark here) objectgraph.com. Of course, this website is nothing to do with O'Reilly Media, Inc. Please use it at your own risk.
I found spoof covers here.
http://letters.oreilly.com/pub/a/oreilly/letters/2001/spoofcovers_1201.html
O'Reilly already made funny covers in 2001.