Bullying has certainly been brought to the forefront of youth/parent issues in recent years. The good part is that an emphasis has been put on resources to help those affected by bullies.
A great website for books and audio material can be located at www.boystownpress.org. That website will link you to the Boys Town Press Department. They have many resources available. You can also call them at 1-800-282-6657 to get a free catalogue sent to you. The on-line catalogue is also available at www.boystownpress.org. In addition, by simply typing bullying into the search engine on education.com you can find many article to help with a youth that is bullying.
Boys Town National Hotline
Here is an article with some suggestions for books to help middle schooler cope with a variety of issues, from bullying and puberty to just adjusting socially to middle school. I hope this is what you were looking for. It may help a child who is being a bully to look at things from a new perspective.