Legal Question in Legal Ethics in California

First, you should keep in mind the statute of limitation for your type of claim. If there's still time to file a lawsuit, use that time to locate the defendant. If the name isn't all that common, you might use one of those search websites to try to find the person. Sometimes, it is necessary to hire a private investigator. If you file a lawsuit, you would need to have the person's address or, after exercising diligence and still can't locate it, you could petition the court to publish. However, then if you win, you'd still have trouble trying to collect on a judgment.