As mentioned earlier, you will not be able to get any information that isn't public without having a legal interest in the property or without having written permission from someone with a legal interest in the property (i.e. homeowner or judgment creditor). The good part is that most of the information you need to answer your question IS public if you know where to look.
I have found that in many of the situations you described the following could be occuring; 1) it is currently going through the foreclosure process which could easily take a year or more in NJ. In this case the courts could be backlogged and the property held temporarily in "limbo" (i.e. the lender in the foreclosure case hasn't yet received final judgment from the courts which would move the case to the Sheriff's jurisdiction to be sold at auction), 2) The foreclosing attorney could be backlogged which results in a stall of the foreclosure as explained in #1, 3) The property owner filed bankruptcy (bk) which will stall the foreclosure until the lender files a motion to lift or vacate the stay thus removing the bk protection the homeowner may currently have against the lender.
If it's been a year or more I'm willing to be that the property owner filed BK. A realtor who specializes in foreclosure should be able to contact both the state and the NJ district BK court to see exactly where the property is in regards to foreclosure (assuming it's still active) and whether or not the property owner filed bankruptcy (respectfully).
Contact me offline if you need me to find out for you.
Ibrahim S. Hughes
EXIT Queens Realty