Getting lists of potential properties for direct mail

[Barry Je]

Many books and people on this forum talk about direct mail campaigns to potential sellers. Currently, I've been driving throughout the town and city looking for apartment buildings seemingly in some disarray, jot down the address, then go on the website for the county and look up the records to find the name of the owner, or, if an LLC, google the LLC to find the owners, and see if I can find an address that way. This is incredibly onerous. Are there other methods people are using that are more effective?

I remember seeing a forum post about obtaining lists...who do I talk to to pay for lists of multifamily properties to directly mail them?  Is it the township, and if so, which department usually can help with that?  Title companies?  

I can see how Driving for Dollars would be worth it if a deal lands, but for someone interested in finding deals out of state, this approach doesn't seem to work as well (unless people are driving on googlemaps to find potential deals?  But even those photos are a couple years old).