Whats the best way to track an "Abandoned" property owners?

[Redgy Saint-Germain]

This morning I went "driving for dollars" and found a really good abandoned property. Its a duplex in need of substantial repairs but well worth it at least from the outside. I`ve tracked down the owners online from the City`s assessors office but the owners address is the same as the properties address. I really want to buy this property but I am stuck. 

There is no historical data, the last sales record was back in the 1950s

I have also done the following:

-Googled the owners name and called a few people and none of them owns the property.

-Checked the city`s website to see if they own any other properties ( Dead end)

Any suggestions?

Redgy