I just finished Nancy Willard’s book titled Cyberbullying and Cyberthreats: Responding to the Challenge of Online Social Cruelty, Threats, and Distress. It is full of good information on this important topic. I think the strength of the book is in the final chapters that talk about legal considerations for individuals, families and schools. There are 2 very good flow charts in the appendix about reviewing cyberbullying or cyberthreats, and school actions and options.
Nancy has done an excellent job at bringing together what little research exists in this arena. The web is still an uncharted arena in terms of how it affects children and adults alike. Check out her website, cyberbully.org, for information on the book and other activities of the Center for Safe and Responsible Internet Use.