An Ebay Seller For Tiffany & Co- How Can I Give Him More Trouble? (more Than Just Complaining To Ebay)?

ok i bought a tiffany ring for my girl, and it turned out to be fake. Very upset, that seller told me he can refund my money. I know that he was selling lots of fake stuff on purpose. Now I don’t care about the $, I want to give him more trouble. Can I take him to the court? I heard about FBI internet agency, did anyone ever try? really useful?
What if I take the ring to Tiffany and give them the seller’s info. will they lawyers do something about it?
I just want to give that guy a lesson and stop him selling these stuff again and again. Any ideas? Thanks