There are 2 airports to get to Tokyo - Narita and Haneda. Narita Airport (NTR) is the main international gateway of Japan, which is 60km from the heard of Tokyo. Haneda Airport (HND) handles more city's main share of domestic traffic and also international flights.
There are 3 major public transportation to get to each airports you can consider.
1. REGULAR BUS
・Tokyo Shuttle (Keisei Express Bus)
Tokyo Station - Narita Airport
¥900 / 70mins
12 row seats and no toilet. Reservations only. This is the one Paolo likes to use for it's price and easy access. This is the cheapest way to get to the airport but you need to walk to the boarding spot from the station. Its 5 minutes away from Tokyo Station Yaesu North Exit. Check out more details at hankyu.j-server.com.
・The Access Narita
Ginza, Tokyo Station - Narita Airport, hotels around the airport
¥1,100 / 80mins
I think this one is a little nicer than Tokyo Shuttle. 11 row seats with a toilet. No reservation needed. Bur once time I couldn't buy ticket because it was sold out so I recommend to go early or reserve. Boarding spot is easy to find, it's right in front of Tokyo Station Yaesu South Exit. Check out more details at accessnarita.jp
2. LIMOUSINE BUS
Airport Limousine Bus
Major hotels, Tokyo Station - Narita Airport
¥3,000 / 80-125mins
If your hotel is listed in the pick-up point, I would take limousine bus even though it's a bit pricy. I'd rather eliminate any troubles before my long flight. Just remember to leave a bit early so you won't be late in case there was a traffic. Get more details at limousinebus.co.jp.
3. EXPRESS TRAIN
Shibuya, Shinjuku, Ikebukuro, Tokyo Stations and others - Narita Airport
¥2,940 / 59 mins
It's fast, and NEVER be late. If you get worried easily about being late for your flight, this is your choice. All seats have outlets so you can charge your phone and PC on the way. Maiko likes it because its seats are big and comfortable. It has no vending machine inside like some bullet trains, so get drinks before you get on.
Nippori, Ueno - Narita airport
¥2,470 / 36 mins to Nippori
If you're staying in Akihabara, Ueno, Asakusa area, this is your choice. It's got toilets, big comfortable seats, outlets on each seats. It's supposed to be faster than N'EX but you can only get on from limited stations, so transit might be a pain. See more on keisei.co.jp.
Are you ridiculously rich? Then take helicopter!
Tokyo Heliport - Narita Airport
from ¥70,000 (you need to get estimate.)
1. LIMOUSINE BUS
Airport Limousine Bus
Major hotels and bus stations, Tokyo Station - Haneda Airport
Since Haneda is closer to the city than Narita, it's a lot cheaper. If your hotel is listed in the pick-up point this could be your choice. Get more details at
Hamamatsucho - Haneda Airport
13 mins to Hamamtsucho
They don't have a nice seats like N'EX and Skyliner, and small luggage space. It's not a long ride, so I usual hold on to my luggage when I take this monorail. When you wait for train, you'll see 2 lines - one for the next train and another for the one after. Follow what it says on the floor sign and don't even think about pissing off Japanese people for cutting in line.
If you're visiting with a group or family, I would consider taxi. Haneda is not too far from the city, depending on your destination, it's between¥5,000 -¥15,000. Keikyu taxi service offers set-fare for each destinations.