On March 18 at 2pm Eastern, the Southern Poverty Law Center will be conducting a live online webchat. You have to sign up beforehand here:
splcenter.org/news/item.jsp?aid=368&splcnewsletter=newsgen-031109

Those participating include their president Richard Cohen and Mark Potok.

Bearing in mind that signing up might end up in you being put on more than just a mailing list for donations, here are a few questions you can ask: