Originally Posted by
ksandness
Some of the subways turn into above-ground trains in the suburbs and cost more, but you are unlikely to go to any of these places as a first-timer.
As an aside, there's one suburban station some people will want to keep in mind- Ogikubo. If you have an AmEx card from home and lose it while in Tokyo, AmEx Japan will issue you a replacement card that day if you report it before... noon-ish, and that's where you go to pick up your replacement card.
I remember because I lost my wallet the first time I went to Tokyo alone.