Not precisely true

> No, there is no way to get a name or address from just an IP address.
> Thank goodness for that or else everyone would be in bad shape.

A lot of business-class IPs are registered to specific organizations, and businesses and schools are usually quite good about starting an investigation if you give them the IP and the time an offense happened. Inside businesses, the IPs are usually static, meaning that a specific workstation or desktop computer can be traced to the employee assigned to that cube. If confronted, the employee might claim they were not in the office at the time, and a co-worker must have used their workstation for mischief, but that alibi can be trivially investigated.

Often the IP appears in spam or other archived material on groups.google.com or www.google.com, and that can provide corroborating evidence of mischief. Or you can sting the perp and their own email reply gives away the location of their day job.

And a phone call to the operator (such as to confirm if a birthday-balloon delivery will be made to the correct address - "no, the employee shouldn't know about this surprise!"), or after hours to a business that runs an employee directory, can confirm if the named suspect works there.

A notorious example from this forum involved a civilian contractor for the US Army using their connection from the armory in his MLM business! It wasn't just reading and posting to this forum, but emails and postings to other forums. Every military facility has a complaint path that involves the Inspector General's staff, and the complaint for this perp was acted upon with speed and vigor.

Static IPs from DSL and cable modem lines can also be tied to individuals if they send email or Usenet postings without stealthing their identity, and subsequently try to send "anonymous" email by way of Hotmail or Yahoo from the same IP. It involves using the search engines as well as having the offending email or posting in hand, but it's a process that's followed by investigators every day.