This link is part of a forum from Sri Lanka, showcasing quite a few celeb pics before and after PS. It is a little dated, but still interesting. Many of the before pics indicate that some of the celebs already went under the knife.
Great idea, la_angel. The only problem is by the time the book was published there would be so many more before and afters to add (part two perhaps?), and the afters in the book wouldn't be up to date!