Hi @Anthony Caiafa - ok, New Jersey uses the judicial foreclosure process, so you'll want to focus on the county courthouses. The process will start with the filing of a court case, picking that up from the courthouse will be the fastest solution. Most service providers will offer tracking of the Lis Pendens - a document filed at the county recorder to encumber the property with the notice of the pending foreclosure. That works too, but will be slightly later than tracking at the courthouse.
If you want to use a service provider, I'd probably recommend Listsource (Corelogic), or Attom Data (the pro version of RealtyTrac). But often in judicial areas, you are better watching the court records yourself.
You do mention wanting to see "inventory" - you won't really find that at the courthouse, instead you'll have to review each case, perhaps going back years, to figure out which cases are still open and active. True inventory tracking is pretty rare. We are one of only two services that do that for non-judicial foreclosures, and I'm not aware of any company that does that for judicial foreclosures.
Hope that helps. As you start digging in to the courthouses you decide to track, feel free to ask questions along the way.