Find the provider that this site buys bandwidth from, check the acceptable use policy and take it from there. If their policy doesn't cut it, then find out who their upstream provider is.
This is AFAIK and it's not 100% acurate but ;
I can "buy" an old oil platform, go to international waters, proclaim to be a state of some sorts, get a "." extension (.seer ;-) ) and run several nice internet servers.. As I don't have to obey US/EU/whatever laws I'm not bopund to TM and @ notices.. AFAIK there's one such old platform out there hosting numerous gambling sites.. Could be mistaken about that tho
Anyway, how do you think to shut down a provider in a country far from yours with different laws ?