By Amy E. Feldman

PHILADELPHIA (CBS) - It used to cost you a quarter to call your best friend to complain about the poor service you received, but now you can just post your complaint on line, and all it will cost you is a defamation lawsuit.

If you want to know about a restaurant in your city, all you have to do is go to a customer review website like Yelp.com and you’ll want to never eat again. Anywhere.

It’s not just food, but also travel, contractor services, or just about anything else that can be rated, is rated, and often horribly on sites like Yelp.

Jane Perez said her contractor was a nightmare whom she thinks may have stolen her jewelry. She warned others online about him. The contractor just sued her for defamation.

Along with the growth in popularity of review websites is the growth of those poorly reviewed, who have filed suits – many successfully.

A California company won over a million dollars this year against a blogger who accused the company of cheating business associates. It’s ok to give your truthful opinion, but remember that the rules of defamation – which is defined as a false statement of fact, made to a third party, that materially affects someone’s reputation or ability to earn a living – applies online and just because you don’t use your real name doesn’t mean you are unidentifiable.

If you have a complaint, you may be better off calling your best friend, rather than putting it down in writing.