I've found a clearer and more up-close image of this book that could be used for the main image:
Lockhart's Guide

Lockhart's Guide to Household Pests possible main image.

AlastorMoody 04:41, August 12, 2011 (UTC)
Could you kindly state where you got that image from? Seems to be fanart, as the photo of Gilderoy is different from that in the actual film. --  Seth Cooper  owl post! 13:38, August 12, 2011 (UTC)

Oh yes, sorry. It probably is fanart, I got it from a website that has Harry Potter prop thingies on it, where you can print out book jackets like Advanced Potion-Making, and even this, so you can print it onto a book. It's here: AlastorMoody 05:43, August 31, 2011 (UTC)