First of all, you need to select a location where you will rent a place and find a person who will be sharing the space with you. Also, decide if you are going to use it for a yearly family getaway. If that is the case, Seaside heights or Wildwood, with their rides and attractions, would be a good bet.
You can then call the guest information centres in selected areas. For that purpose, you can go through the local phone book. You should have more than one location chosen in case your top choice is taken. The information centres will often know the newest resorts opening and who has promotional deals. Sign up for newsletters for the resorts you are considering as these will have new vacancy notifications.
Some timeshares offer specific dates and others have floating weeks, which means you have a certain amount of time you can use as long as no one has claimed the time you want. The most desirable dates go fast. So, you should consider that before deciding on what timeshare plan you want. Mark the days on a calendar and then look for the share plans in your desired dates.
Some resorts will let you stay for free for a day or two in order to pitch their accommodations. Explore the area and talk to some locals and vacationers to get a feel for the place. If you visit before or after the summer try to imagine the place packed with parties, revellers and other vacationers. New Jersey is the most densely populated state in the nation and nowhere is that so obvious than down the shore in summer.
You should carefully pay attention to the share agreement regarding the rules related to the use of facilities and maintenance of the rooms. If it is a complex agreement you may want to consult a lawyer. Follow the agreement and be a good neighbour.