Don Tepper- Thank you so much for your time and consideration!! I thought that a realtor might have such information. I'll make a note of your advice- and thanks so much again!!
What you're looking for are what's called "absentee owners." They may own a property at 123 Main Street, Olney, Illinois, but their tax bill is mailed to 456 Maple Street, Columbia Missouri.
How do you find them? The easiest way probably is through a Realtor. It's easy to go in to the MLS (actually, the tax records linked to the MLS--in most areas) and specify absentee owners. At the same time, you an establish whatever other parameters you want--number of bedrooms, whether the property is a single-family home or townhouse, age of property, etc. In my area, the information can be downloaded in CSV format, so it can be imported directly into a database or Excel. Or it can be exported in label format. Each MLS is slightly different, so the one in your area may have more capabilities . . . or less.
If you don't want to use a Realtor, you probably can accomplish something similar--though with perhaps more work--yourself. Most jurisdictions have their tax records online. Some are in downloadable format.
If that doesn't work, there are plenty of list rental companies that'll sell that information to you.
Hope that helps.