Resources: http://www.japan-guide.com/e/e2164.html http://www.tourism.metro.tokyo.jp/english/

Tokyo is generally a good introduction to Japan, but it is not all that Japan can offer :) It's mainly a metropolitan city good for shopping, dining and a little culture on the side.

So how do I get to Tokyo?
from Narita Airport
There are many good and cheap options you can take to Tokyo City from Narita Airport.
Do remember that Narita Airport is in another prefecture! It's not like Changi Airport in Singapore.

I'll explain the individual package deals in another post.

1) Narita Express (aka N'ex)
This is a very good line run by JR. It's fast, comfy and stops at major locations like Shinjuku Stn, Ikebukuro Stn and Tokyo Stn. Plus with the Suica-N'ex package, it's a great deal.
It's not as frequent as the Keisei Ltd Express. Plus price wise, without the package I personally feel it's expensive.

I highly recommend this to anyone, if they are also interested in the Suica.

Do note that not all trains stop at Ikebukuro.

Timetable here: http://jreast-shinkansen-reservation.eki-net.com/pc/english/common/timetable/index.html

2) Keisei Train Lines
There's the Keisei Skyliner, Keisei's answer to the N'Ex, and the Keisei Ltd Express.

The Keisei Ltd Express is actually just a normal local train line. Its cheap and very frequent, but being a normal local train you don't get comfy seats like the Skyliner and the N'Ex. It takes about 30mins longer than the N'Ex to reach JR Tokyo Stn, plus you need to change trains at either Nippori Stn or Ueno Stn.

The Skyliner is quicker and more comfortable than the Ltd Express, but you will also need to change trains at either Nippori Stn or Ueno Stn. It is also cheaper than the Narita Express.

The Keisei lines, in order to compete with the N'Ex lines, come with a package that includes a 1-day Tokyo Metro pass.

Timetables can be accessed here: http://www.keisei.co.jp/keisei/tetudou/keisei_us/top.html

3) Airport Limousine Bus
This is the most convenient public transport route.
It drops off at various hotels and stops near hotels, so you won't have to bother with trains and luggages at the same time.

Problem is... it's expensive and rides back to Narita airport needs to be reserved in advance.

It takes longer than the trains to reach Tokyo City and it's also subjected to traffic conditions. But i have to emphasise that it is very convenient, especially if you have huge luggages.

It also has a tie-in with Tokyo Metro, so you can get a 1-day Tokyo Metro pass if you get the package.

4) Taxi
Unless you are bleeding money, this is not an option.. EVER.
It's freaking far from Tokyo costing about 25000yen one way.

To put into perspective, with the bad economy and the resulting horrible exchange rate of 65yen per SGD.. thats S$384.62

If you would like to spend that much money on a cab.. by all means :)

Haneda Airport
This airport is located within Tokyo city itself, which explains the much cheaper price to commute there.
But they handle only domestic flights.

1) Tokyo Monorail
This train services Haneda airport via Tokyo's Hamamatsucho Stn, located on the JR Yamanote line.
It's fast and reasonably priced.

2) Keikyu Line
Connects to Tokyo via Shinagawa Stn, located on the JR Yamanote line.
This is also fast and slightly cheaper than the Tokyo Monorail.

I guess for which to choose, it depends on which station you are staying closer to.

3) Airport Limousine Bus
Same company and concept as the Narita's buses.
It's convenient but very expensive as compared to the other 2 options.

From Other major cities in Japan

Well, you have 3 main options. Domestic flight, Shinkansen or Highway buses.
Local trains are also possible, but take a much longer time and are not always cheaper.

From Osaka, Kyoto and Nagoya, you can take the Tokaido shinkansen.
From Fukuoka and Hiroshima you can take the Sanyo Shinkansen and transfer to the Tokaido Shinkansen. Some lines are direct.
From Tohoku you can take the Tohoku Shinkansen.
The list goes on :)

And.. there's the option also of saving some moolah and taking the highway buses.

It's cheap and most of the time direct.
I'll be dedicating a post on Highway buses. So read up there.

There is also the option of taking a domestic flight which may land in Narita airport or Haneda airport.

To round off... for all train changing and train costs and details... Use this website http://www.hyperdia.com/ Will also dedicate a post on that. Look out for it!