In Illinois, we have something called Realist that an agent can sort by pre-foreclosure or bank owned. Pre-foreclosures are probable short sales and bank owned are REO';s that are listed.Check with your local agents, find someone competent that you like and stick with that person. They can be your best advocate and help you find and negotiate a bank owned house. Often REO's are priced low and get multiple offers the first week. So going it alone doesn't work well as to being quick to see and write offers. The good inventory sells fast at or above asking price and the bad sits there. So you need to keep abreast of new one's that come on.
Can be tricky depending on where it is in the process. If it has been bank owned for a few months, it may show up on the tax records. The way you would know, is that a financial institution would be listed as the owner. This site allows you to search NJ Tax records for free: www.njactb.org
Also, you can search the country sheriff website. You'll want to look under "civil process" or "foreclosure" you should be able to search on the site specific address, and you'll be able to see when they got foreclosed or where they are in the foreclosure status.
If they are listed they can be found on either a bank's or third party servicer's website who is handling the asset or a good Realtor can help you find out.