Narita handles the majority of international passenger traffic to and from Japan, and is also a major connecting point for air traffic between Asia and the Americas. 

You will find lots of useful information on their own website.

Transportation.
Narita International Airport, a representative gateway to Japan, is located some 60km from the heart of Tokyo. It is convenient for those who will go directly to Haneda Airport to take the direct limousine bus service (one hour and 15 minutes) or the Keisei Railways' Airport Limited Express (one hour and 45 minutes). 

Limousine Bus
Airport limousine buses have extended their routes to the new terminal, and now offer late-night and early-morning services. Bus services have started on new routes, linking Haneda with many hotels in areas such as Roppongi, Ebisu, Shirokane, Shiba and Shiodome. To check the routes, click here. 

For other transportation between Narita and Tokyo see here.