Marcin is correct with the directions however the costs are different. The Airtrain from the airport to the subway is $5 and the subway is $ 2. The Greyhound Bus from Port authority is $ 25. You can view the bus schedule and fares and luggage charges and limitations @ www.Greyhound.com The Greyhound bus takes about 2 1/2 hours. The subway ride is about 45 minutes but you might have to wait for a train at night when you will be traveling for up to 30 minutes. Another alternative is to take the Express bus from the airport to Port Authority Bus Terminal. The cost is $ 13 but it might be worth the extra $ 6 if you are carrying luggage. The bus to Port Authority is aboub 45 minutes to an hour You can find that information on this web site. click on Bus on the right side.
Steve
To Atalntic City