I used Newark and didn't take long to get in. I used the taxi marshall people who agreed a price in advance though we had to pay tolls on top of that and there is a bit tipping culture and you are meant to tip a certain amount on top of the fare as standard - if you don't, they are likely to tell you so!
Make sure you have lots of change on you as unless it's a large amount, you aren't likely to get much change back anywhere service wise and make sure you have lots of dollar bills handy for tips and get a good handle on how much you are meant to tip for what (per drink in a bar, taxis, food etc...).
If you don't want to pay for bellhops to take your bags anywhere, keep a good grip on them as if they help you then they will expect a tip over a certain minimum. Depending on the hotel, there may be a clamour to get your bags if you put them down.
It's an amazing place though! If you want the Empire State, go early and don't get ripped off with the street touts. It takes a fair while to get up top with scanners and different elevators, regardless of the queue.
Top of the Rock is great at night and some of the bus tours are fantastic, we got a package deal and did uptown and Harlem, downtown and Brooklyn and a night one (including the Hulton Ferry crossing for the skyline at night). Some of the tour guides are fantastic (and encourage tips :)).
If you don't want the cost of Ellis Island for the Statue of Liberty, the Staten Island Ferry gives a good view and it's free!