How to find
In any case, it is very difficult to find.
Completely legal option - by the police, but they won't be.
And so you can look for yourself, or to hire people, if the money is not a pity to spend it.
to punish the owner of the site
The only legal option to sue him in court.
For this you need to gather evidence of his guilt, but it should be remembered that the court is not cheap, and you can lose.
All other methods illegal - kick, to hire specialists to stuffed muzzle, etc. and with high probability provide priverzhenka these methods the way in places not so remote, in full gosobespechenii.