Where can I report personal property tax evaders?

The problem is not just local. I saw a 60-minutes piece not long ago about corporations who have their headquarters in other countries to avoid the federal taxes on profits here. It was unreal. Most of them had a mailbox, shared with many other companies, or simply and office space with a receptionist. No one worked there. Nothing was produced there. BUT, it kept them from paying the higher US taxes. Very frustrating for people who pay their taxes and do things correctly. The rich get richer, the rest of us get .....well, you know.

http://www.cbsnews.com/stories/2011/03/25/60minutes/main20046867.shtml

http://www.hrworld.com/features/10-overseas-companies-060408/

http://www.minyanville.com/business...tune-500-vale-disney-kraft/7/16/2010/id/29187

http://www.commondreams.org/headlines03/0527-08.htm