Are you looking for a particular landlord or a whole list of them? If just one (or a few), you could go to the assessor's office and get their contact info from the property records. If you're looking for a whole list, you'll likely have to buy it (i.e. absentee landlords). But there's no way that I'm aware of to identify which ones have a PM and which ones don't since that information is not recorded anywhere.
go on craigslist and start contacting those people posting ads. It's pretty easy to tell the difference between professionally managed ads and those from mom and pop landlords like me