Next steps in extortion case - ideas?

[universe at truemetal.org (Markus)]

Am 28.06.2014 19:44, schrieb Rob McEwen:
> You mentioned that this person resides in the US. Does he always target
> people outside the US? (from what you know about him)

No, he targets individuals and companies all over the world in this 
particular area of business.

And that's another good aspect. Because my goal is to shut down his 
activities as a whole, and not simply remove the blog posts about 
myself. The blog is hosted at blogspot (Google), and I see that they 
every now and then remove single posts after someone complained for long 
enough, but I guess the blog as a whole falls under some kind of freedom 
of information thing, so Google won't shut it down. And even if they 
would, he'd simply switch to another blog provider.

Regards
Markus