If you live in U.S. and if they live in U.S., best way to go is file a lawsuit, but if they live in countries such as Russia, then there isn't much that you can do or if there is, it's probably going to cost more following them than just leaving them. Don't know.
Nice website btw. Is it a template or your work ?
There really is little point in reporting most hackers, even if they reside in the same country as your server. For every hacker you report, there will be another 1000 out there capable of doing the exact same thing. I'm not saying, don't abide by the law and report criminals, i'm saying don't put your servers in the vulnerable position in the first place