Here is a good article on how to handle bullies at school:
http://www.suite101.com/content/bullies-parents-students-and-preventing-school-violence-a241177
And another regarding bullying among girls:
http://www.suite101.com/content/the-drama-and-trauma-of-bullying-among-girls-a240640
And another article on CyberBullies:
http://www.suite101.com/content/cyberbullies-harassing-kids-in-the-new-age-of-technology-a241301