We just returned from a trip to Tokyo a few weeks ago, and we took the Keisei Skyliner from Narita into the city, and got off at Nippori to transfer to the JR Yamanote line. If you are going all the way to Shibuya on the JR line, then I'd make a guess that that will take you 45 minutes (this really is a guess, but Shibuya is on the opposite side of the city), plus the Skyliner trip is about 50 minutes (plus the Skyliner trains are not particularly frequent).

There are other trains from the airport to the city, but I had gotten the advice that the Skyliner is the best value, and at any rate it worked out well for us.

Danak:
Why not catch the Limousine bus service to your hotel. Just checked and they have door to door service right to your hotel. Check http://www.narita-airport.jp/en
click on the taxi and bus service. Click on the airport limousine bus link and it shows that the service is direct from Narita to your hotel in Shibuya. Cost is 3,000 yen per person and takes about 80 minutes. I used this service a couple of weeks ago. It is very convenient, they load and unload your luggage for you and you don't have to worry about the train and all those hassles. Theey are located right as you get out of customs and the buses leave from right outside the door. Hope this helps!

There are several trains from Narita to the airport. The skyliner is the fancier one, 2000 yen, runs every 40 mins, takes about an hour. There is also a regular Keisei express which costs only 1000 yen, runs every 20 minutes, takes 10 minutes longer (about 70 mins.) The JNTO booklet on Narita Airport lists all the alternative methods of transport. The green ticket window at the airport will also give you all this info in English, very well organized.
The JR Yamanote line runs in a circle around Tokyo and stations are clearly marked. The tricky part may be when you get off the train, but just ask someone for help. The Japanese people are extremely helpful with directions.

I just got back last night (or is it tomorrow morning?). I agree w/hawaii. Even though we had activated our JR passes at Narita airport and could have taken the NArita Express w/the pass, we would have had to change at Tokyo station w/out luggage. We alos got yen at the ATM at Narita, and made reservations for the trains we wanted to take during out 2 wk trip, plus it took 80 minutes to get through customs. After the flight and all of that, plus a stop at the TIC, there was no way I would have dealt w/changing train lines and walking to the hotel, even a few minutes. We opted to take the limo bus for $30 apiece, a real bargain. We never touched out luggage after we got it on the luggage cart at the airport- the bus fella loaded it on the bus, the driver got it off. We had been awake 24 hrs. by the time we got to the hotel.

please excuse the typos. I am a tad jet lagged, although not too bad, but I left my glasses on the plane on the way home and it is all pretty blurry right now.

to me it's better to take the limousie bus if it goes directly to your hotel even it takes a little longer. the jr stations are not friendly for folks with luggage. if you want to take the jr train, pack lightly.

Should i worry about traffic and it lenghtening the time it takes to get to our hotel. We arrive at Narita at 1pm so i really shouldn't expect to be at the hotel till 4ish?

What day of the week are you landing?
Also, what else do you plan to do at Narita besides go through customs and get your luggage? Do you need to use the ATM and get yen? Make train reservations or activate a JR pass? Go to the TIC? Rent a cell phone?
Even if you don't have to do any of those, you may not be right on time for the bus getting ready to pull out. You may need to wait up to hlaf hour for the bus.
Plus I will add that when out flight landed it landed it taxied a l-o-n-g way to a very remote area of the airport, far far away from any terminal. They unloaded us off the plane in the middle of nowhere, and got a bus to shuttle us to the terminal. Well, one bus wasn't enough, and from what I could tell they weren't sure they coudl get another one there soon enough so they first tried to squeeze everyone on one bus. Once it became apparent they couldn't do that, they still wouldn't let the first bus leave for the terminal til the 2nd bus arrived and all the extra passengers got on it. All of that in itslef took 45 minutes, just to get us to the terminal. Then 80 min. wait in line for customs. Then find the correct counter for bus and wait for bus. That in itself would have taken us 3 1/2 hrs, then another hour for the bus ride.
Combinbed w/the ATM and JR office and the bus ride- we finally got to the hotel at 10 p.m. And we landed at 4:30 p.m. And this was a Sunday night.

emd - i really hope we do not have the same experience as you. We are flying in on a Tuesday (land at 1pm) and leave the next day at 4pm. All we will need to do is get our luggage and get in the bus or train. I really hope we will be ok. Don't want to spend my 28 hrs in Tokyo in the airport.

Oh goodness, it's a quick trip. We were on Northwest Airlines, and I can say that their disorganization w/the bus thing did cost us extra time. But the customs deal isn't really something you can change. Usually I hear it takes about an hour for customs. I really hope your experience is better so you can maximize your time. Since you are only staying overnight, you won't have alot of other stuff to do at the airport (except maybe find the ATM to get some yen? that is easy)
I don't want to add insult in injury, but I feel compelled to tell you that getting out of Narita was not easy for us either. We arrived 3 hrs before our scheduled flight (which was back to the U.S.) I thought we'd have lots of free time. But instead, it took us all three hours to do the following: get through lines at baggage security, then get to the crowded eticket kiosks, then the crowded ticket counter to check bags, then get through regular security for carry on and person screening, then get to the gate. By the time we did all of that, we had no time to eat and it was time to board the plane.
Let us know how it goes. I've got my fingers crossed for you. Maybe it was particularly bad since we landed and departed both on Saturdays.

emd said > when our flight landed it taxied a l-o-n-g way to a very remote area of the airport, far far away from any terminal.

That's so true when you land in Narita.

> They unloaded us off the plane in the middle of nowhere.

That's surprising. I have never had this.

> 80 min. wait in line for customs.

Persoanlly I have had nothing close to that long wait. Maybe that's because I usually arrive in early am, 8:00-10:00. For example, in my last trip (this feb-mar), my plane landed at 09:30 and even with a interminable taxing, I got out of custom by 10:30 and took my limousine bus of 11:00. Almost no wait at immigration nor custom and luggage pick up was rather quick. Of course you can say I know the way as it's my home and I do that once every year. I found myself in the center of Tokyo by 13:00. Well that's still 3-hr+ long way.

Actually, now that I stop and think about it, it was Sunday afternoon at 4:30 p.m. when we landed (not Sat., it was Sat. when we left the U.S.). So maybe it was Sunday when alot of business people fly in to Tokyo for the week? Maybe that's why customs lines were so long.

i hope that we have an easier time. My husband and I are both Continental Elite members so hopefully we won't have to wait in the crazy long lines to check in.

Can you guys suggest anything for me to do in Tokyo - the only thing i have planned right now id the Tsujiki fish market the next morning at 5am and then we'll go go go until we have to go to the airport which will probably be around noon. wish i had more time there.

You could leave your luggage at the airport overnight. Something like 500 yen per bag. When you come into the arrival hall turn left and you will see ABC and other luggage services. Just take what you need for the overnight.

Can you check-in online with Continental?

mrwunrfl - i have heard u can leave bags overnight and I think we will do that. Usually you can check in online with Continental, but with an international flight, we can't...I wish we could send our bags through on continental and then pick them up when we arrive in Newark. Will try and do that, but who knows...