I will explain the most standard way to come to Sendai.
Just ask a one-way ticket for Sendai with Narita Express and (Tohoku) Shinkansen. More than 15 minutes is recommended for the transfer at Tokyo station. (This is for safety. I can do it within about 5min but not recommended. The Tokyo Station is a huge complex.) You need seat reservation for the Narita Express and are recommended to make seat reservation for shinkansen too. For Tohoku Shinkansen I recommend to choose "Hayate" (The most rapid) or "MAX" (the second). I believe that there are still smoking cars.
It takes less than 50-60 min from Narita AP to Tokyo. The Tokyo station is not necessarily the final destination. It costs about 4500 yen. The green car (first class) costs 50% more. There are local trains from the airport to Tokyo but not very recommended.
The Narita Express arrives at a very deeep level of the Tokyo station. Follow the sign ``Shinkansen" and in a few minute you will come to the gates for the Shinkansen. There are many Shinkansen with different directions. You must come through the gate for Tohoku Shinkansen (signed in Green).
For ``Hayate" the most rapid train you need seat reservation. It takes about 100 min from Tokyo to Sendai with just one or two stops (near Tokyo) before arriving at Sendai. There are slow Shinkansen trains (stopping many stations) which take 120-150 min. The price of the ticket is about 10000yen and the Green car (first class) 50% more and certainly more confortable. The through ticket from Narita AP to Sendai costs about 13000 yen (Green car 50% more).
Upon your arrival to Sendai Station, come out through the West Exit (or Main Exit). You are recommended to take a taxi to your hotel. The Sendai Excel Hotel Tokyu is in fact in walking distance (15 min). Walk along the Aoba Dori Street from the Sendai station. The hotel is located on the left side. map provided by the hotel
There is limousine bus service for the Sendai station. Near the Exit No.1 of the arrival hall you find a small ticketing machine for the limousine bus. A staff is always around the machine. Please buy a one-way ticket for the Sendai Station (910 yen). Most buses terminate at the Sendai station after stopping at a small minor stop (only few people get off at this) and a one very close to the Sendai Station. Some evening ones run further after stopping at the Sendai station.
Upon arriving at the Sendai Station, take a taxi or a walk to your hotel. See the last paragraph in (1).
The limousine buses departing at 18:05, 18:30, 18:55, 20:15 stop at very infront of the Sendai Exel Hotel Tokyu (the name of the bus-stop is Bansui-Sodo) after the Sendai station. The time table is rather flexible due to the delay of flights. Please check the staff or the bus driver.
You can come by bus or by taxi. The buses might be slightly difficult to use the first time. A taxi to the GSIS costs about 2000 yen.
To take the bus, the trip begins at the bus pool, which is located in front of the station and just to the north of the Hotel Metropolitan Sendai. There you will see many bus stops, marked by rectanguloid posts numbered from 1 up to the 30s. The W7-1 bus (AobajousiJunkan), W8-2 bus (Miyakyoudai), W8-3 bus (Aobadai) and W8-4 bus (Naritasan) go to Tohoku University and leave from the post marked with a 9. The W7-1 comes about once every half hour or more, and once every twenty minutes during rush hour. The W8-2 also comes about once every half hour or more, and further, once every ten minutes during rush hour. The W8-3 comes about once an hour and the W8-4 is very few - comes five a day. Boarding at the rear door of the bus, passengers take a white slip of paper from machine located just inside the door. This white slip is used for deterimining the fare that must be paid at the end of the trip. For this trip the fare is 220 yen, and it is best to have exact change ready. The stop you get off at is about 10th or 11th stop (depend upon a bus). It is the stop called the JouhouKagakuKenkyuka-Mae. ``JouhouKagakuKenkyuka'' is Japanese for ``Graduate School of Information Sciences" and ``Mae" is Japanese for ``in front of'', and anyone on the bus will understand this word. So, you can see our building of Graduate School of Information Sciences from the bus stop. The Division of Mathematics is in the 6th and 7th floors in this building. See also GSIS-MATH