Arriving at Newark Airport is quite easily to catch the local train into Penn Station Manhattan and from there the Underground will take you to mostly any part of the city. (The best buy of the city must be a seven day Metrocard at $25. it takes you from the Bronx to Coney Island and many other places too)
Just stepping out of the station causes your jaw to drop in amazement at the buildings, the lights and the traffic.
Must visits are the Empire State Building, Staten Island Ferry (Free), Battery Park, Central Park, Grand Central Station, and Times Square. If you crave a little indulgence try a helicopter flight over the city, it is as the Yanks say "Awesome". No doubt the shops will temp you to part with a few dollars too.
I found the locals to be very helpful, don't be afraid to ask for directions or help, it might be difficult to find an English speaker, but they are very helpful and keen to meet people.
