If you want to know the ownership, there are companies that will perform that for a fee. You start with what the name on the FAA records says. It will either be a US individual (LPR or citizen) or a corporation/LLC/Trust with US entities controlling it. Of course, if the entities are in jail or otherwise unavailable to you, you're screwed.

As pointed out, even if they signed over the title for nothing, you like are going to have more to put in to it than it's going to be worth. The engine alone can swamp the value of an older Cherokee. Add to that everything made of rubber (tire, fuel lines, seals in the carb, etc...) are likely to need replacing. That doesn't even begin to address the nightmare if there is corrosion. While Cherokees don't tend to have a whole lot of ADs on the, there are a few onerous ones (like the wing spar) and if that's not been done, you'll have to have it done (and if necessary fixed), before any IA will sign off the annual. It goes on from there. A poorly researched aircraft is no bargain.