Actually I`m very generous with it comes to copying my web page content. What I only ask is put a simple note in their website where did they copied that article. I`m not asking for a live link just a text of the URL, enough to let their readers know that the article that they are reading was just copied from other website and they don't have authority over it.

Anyway, I tried to email them first to remove the file. If nothing happens, then, let's see....

If there's no way to contact them then they have given you no choice but to follow through with a DMCA. But even a proxy registration has an email addy listed in the whois info. In my experience most people respond positively to an email or phone call.

I've been a victim of university speakers posting my content online attributed to themselves (with links to my competitors), of amazon.com's askville illegally hosting my content, and even google's blogger hosting the same content, all with the effect that google doesn't recognize snippets from those pages as originating from my site. So it's absolutely critical to check for plagiarizers and to get them to take down your content. In my experience contacting them directly will get a faster response.