Do you mean Newark Airport or Newark?From the airport, you can get the Airport Express bus to Port Authority and then walk or get a cab to your hotel. You can take the AirTrain from your terminal to the Liberty/Newark Airport stop and then get a NJ Transit train to Penn Station New York. You can get the PATH or a NJ Transit train from Newark Penn Station. A car service would run close to $100, there's tolls and tip.
Anything else will cost nearly as much as one night in your hotel, or one discounted Bway ticket.Edited: 12 December 2017, 22:18