Locating/contacting owners

[Glenn Mayo]

I hope this question is in the right place. I haven't seen it asked or answered anywhere.

How do you locate an owner of an empty property you want to buy? Let me clarify. I know to search the tax records of the county in which the property is located, and generally, that will get you the name of the owner of the property. But once you have the name, how do you go about finding that owner's phone number, if it's not in the white pages? And, if you can't find the phone number, what is the best method of contacting that owner, if the only address you have for him is the property's address and, CLEARLY, no one lives there?