One of the best things we all can do is inform ourselves on the mindset of these criminals. PETA is the group we all have heard of. But the Earth Liberation Front (ELF) and the Animal Liberation Front (ALF) house some of the more violent sickos. Both those groups have been responsible for numerous acts of terrorism both domestically and internationally. I put a link down at the bottom to ALF's primer for direct action. While PETA has definite spokes people and tries to pass themselves off as a legitimate political group, ALF and ELF stay a lot more shadowy. They operate with a "leaderless resistance" methodology... just like Al Quaeda. Individual cells are resonsible for conducting autonomous actions. Read on for anyone that is interested:
http://www.animalliberationfront.com/ALFront/ALFPrime.htm