A search engine doesn't show me on the internet because I don't post any personally identifiable information online. The only exception is Classmates.com but the information is vague and only usable by subscribers. On my work site I have my name but it's a .jpg file not searchable text. Internet searches for my real name show only other people with my name, none about me. I've worked hard on that.

If someone were to spread information about me online and a client (or employer) were to use that information against me (try to), I could sue. Proving that's what they used might be difficult.

The best defense to slander is living a blameless existence. If you have a guilty conscience or what they're writing about is TRUE, well... who is to blame for that? Surely not the reporter. But anyone can say anything and it just being online makes people believe it.

I wouldn't validate the slander by acknowledging it in any way, you'd just bump the link further up the search list by linking to it. But if you are one of those people who has a blog you could always post something that a careful reader will be able to discern as what really happened but don't do it out of protest to the slander, post it generically.

Example: If the slander was about you and that other person seen at a party and how drunk you got, you merely post an entry about that same night (whether you were at the party or not) and casually write about the entire night, barely mention the other person (if in fact you saw them), and how much fun you had. That way if someone does think it's true and they read your blog they'll find (if they dig for it) YOUR side of the story without it looking like you're being defensive or upset.

Personal slander I can live with to a point. Professional slander is what I pay insurance to protect myself from and hiring a lawyer to pursue them is necessary. Don't let even the smallest threats or rumors get a foothold.