how purchase JR East Pass outside Japan?

I'm going to Japan in October 25 and I'd like to reservate JR East Pass. How is it possible to purchase it from internet?

You will need to allocate a travel agent first who sells the Pass preferably in the country you live. ( JR East does not sell directly or on their homepage. ) Then check if this travel agent accepts booking via their webside or e-mail address. Where are you from? If it is too diffcult you can buy the JR East Pass after your arrival in Japan. See: http://www.jreast.co.jp/e/eastpass/obtain.html

I'm from Estonia, so we don't have any of these travel agents in our country.
But are these offices:
1)Travel Service Center (Marunouchi North)
2)Travel Service Center (Yaesu Central)
3)Ticket Office
in Narita airport also???

Thanks for your answers

Sry already found Narita terminals from this list.

Thanks a lot, problem solved

Peter from Estonia,
oK. Sorry to mention it and by no means I want to interfer with your travel plans. But you are sure the JR East Pass is the right one you want? You only want to make long distance travel East and North of Tokyo and no travel on the more 'classical' route of Japan to Kyoto, Hiroshima. If you let know of your travel plans maybe there is a better Pass for your purpose. ( For example do not use the one day out of a 4 day flexible pass what is Yen 5000 value just to go from Narita airport to Tokyo accommodation and around inner Tokyo, this can be done cheaper. A day trip to Nikko can be done cheaper by a Tobu Nikko World Heritage Pass incl entrance fee at Yen 3600 than a day's value on the East Pass without entrance fee ( plus Yen 1000) ).

My trip plans are: to arrive Narita. Then to be in Tokyo for 2 days, after that I need to go to Sendai (the best way is to go with bullet train from Ueno if I'm correct??), then I'll stay in Sendai for 4 days and after that 2 days in Tokyo again.
At the end go back to Narita and home.
So if I'm correct, the cheapest way to travel this course, is to buy 10-day JR East Pass and thats about it...
Please correct me, if theres a more cheaper or easier way to do this trip

Waiting for an answer :)

As you travel to Sendai yes JR East is good. ( Tokyo - Sendai by shinkansen is Yen 21 500 return ) But you may consider the flexible 4 day Pass at Yen 20 000 instead of the 10 day at Yen 32 000. Use two of the four days for Tokyo Sendai and Sendai Tokyo and the other two days maybe for day excursion to Nagano and Matsumoto castle or Ito and Kamakura. Within Tokyo and within Sendai it is very unlikely you will need a total of yen 12 000 for travel on JR trains. Within Tokyo you have several non-JR trains and subways.
As I count your days in Japan as 8 ( ? ) even a 7 day JR Rail Pass ( plus one travel Narita - Tokyo paid locally ) for all Japan is cheaper than the 10 day JR East Pass. Disadvantage the 7 day JR Rail Pass at Yen 28 300 you can only buy outside Japan.
The shinkansen goes Tokyo station - Ueno - further stops - Sendai, so you can board either at Ueno or Tokyo. You can visit Nikko on your way to Sendai by a stopover in Utsunomiya and then local JR train to Nikko.

hmm. Good thinking. I'm actually in Japan because of work, but some sightseeing doesn't harm.
I'll have to calculate and think about that 4 day flexible ticket.

But thanks very much for that information. I'm a lot smarter now :)