Home not listed on county property appraiser site

[Patrick Jacques]

There is an empty home, which I can see out of my back window that I've had my eye on for a while.  It exists on the typical sites such a Zillow and Trulia.. but not on the county appraisers site.  How is that possible?  Id like to find out if it's an absentee owner or what is going on with the home.