An attorney friend asked me how to identify a blogger or possibly get their “ip address.” My answer:
This is difficult to do, but it’s an interesting question. There are two main ways to write a blog: (a) at a blogging platform like wordpress.com, or (b) at a personal / corporate custom web site.
The only methods I know of for identifying the blogger in scenario (a) are
- A subpoena;
- detective work, i.e. using clues in the content to figure out who & where the person is.
In the case of (b), the custom web site, it’s a lot easier. This is because the blogger will probably be connected to the registration of the domain name as well as the organization itself.
Another idea: I once identified a person who was stalking a friend by looking at technical clues in emails the stalker sent. I did it by examining the usually-hidden portions; the “message headers”. So if your victim has received emails from the antagonist, they could contain helpful info.
Note that if this is a copyright, trademark, or possibly even defamation matter, then the person’s identity isn’t as important. One can deal directly with the webhost and ISP using DMCA-style takedown notices.
Dogweather 
This article is a good start, but emphasis on the fact that blogs do not disclose the I.P address of the author in the same way that the above mentioned email headers.
Furthermore, the subpoena process above runs a risk of the important log file evidence perishing. If a blog site is subpoenaed, after getting past 30-day user notice delays, resistance etc, the blog can only provide the user’s IP address (assuming the user used fake registration details). All the while the actual ISP’s log file records are getting closer to automating deletion (only 7 days for some telcos).
By necessity we have had to develop proprietary techniques that can reduce the need for subpoena, and the associated delays; often positively identifying the antagonist within 24 hours. The techniques are legal and admissible in court.
Respectfully submitted,
Michael Roberts
Founder
Victim’s Advocate, Forensic Analyst and Litigation Support Consultant
http://www.rexxfield.com
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