Something that you need to definitely have to do when you divorce is watch yourself, and watch your name. Google it if you have to. I have personal experience with this phenomenon.
My present girlfriend had the wonderful experience of being stalked by her ex. He started a website solely for the purposes of trying to make my girlfriend look bad, put her down, and talk about personal information. He would put pictures on his site and allude negatively towards her work habits, personal experiences, and et cetera. Absolutely a prince, you might say. Eventually, it took a threat from the FBI, local law enforcement, and various websites being pulled from free sites for violations of terms of service to make him cease and desist.
My ex is similar, but does a different kind of stalking. On her MySpace page, (a page that which I read regularly) she describes how miserable she is and attempts to slam me as having a drinking problem and being an irresponsible and deadbeat dad... despite my regular OVER payments for child support - never missing a payment, regular visits, and general overall support. The reason that I am not with her is that we don't get along. I DO want to be with my child 24/7. It's a huge difference, and an emotionally and legally expensive one. Update! After talking to the offending person, she agreed to remove the offending content, which is great. She didn't, and just made her pages private, but hey, that's better than a poke in the eye. We'll see.
Solutions? I'm not sure that I have one, and if anyone has any great ideas, then I'm all ears. I'm already considering legal action. However, if your breakup with your ex was acrimonious, then learn to use Google. Be your best private detective. Keep a journal It can be a little annoying and perhaps may cause you fume a bit, but make sure that you have all the possible information. At least that way, if you decide to follow through, then you'll have all the information. Over at WiredSafety.org, they have a lot of great information about cyberstalking and a number of other Internet crimes.
Here's one that you can write down; despite any odd thing that I might see in her behavior, actions, or choices, you will never see me slam her in print. That's no better than gossip, and despite the fact that our relationship didn't work out, she does have good qualities for someone else. That won't stop me from being the dad of a three year old.
Remember as well; self improvement is the best form of revenge.