1. Search the Multiple Listing Service (MLS).  The MLS contains homes that are listed by a Realtor and it also contains a few homes by homeowners who pay a fee (usually $500) to be listed on the MLS. 
    
2. Search other services which specialize in listing homes for sale by owner.

These homes are not usually listed on the Multiple Listing service, so they offer home buyers an additional source of homes for sale in New Jersey.. 

Bargain.com seems to be the best deal with a 7 day free trial period and $9.95 a week after the trial period expires.  It's a great service, but don't forget to cancel once you are have found your house! Additionally, they appear to have the largest database of For Sale By Owners in Manhattan.   Check it out by clicking on the banner below!