Here’s a pretty good article (actually it’s a Wiki, contributed by several authors) about how you can manage your Facebook profile and friends.
Read this article if:

You (you dinosaur, you) are still contemplating whether or not to join Facebook because you’re worried about ‘privacy issues’,
You feel that Facebook is “too personal” to link up with colleagues or business partners,
You’ve wondered whether or not to “friend” your ex,
You’ve had friends who post stories about sexual escapades, drunken moments, and racist comments on your wall,
You’re trying to decide if you should “friend” your …