Originally Posted by
thumbun
... Want to take the train from Tokyo to Kyoto on Monday, December 28th. Is there any way to reserve and/or purchase tickets outside of Japan?
No.
Best to make your reservations immediately upon arrival at NRT (assuming you are arriving at NRT.) There is a JR office in the arrivals hall but I always use the ticket sales office at the JR station in the basement of the arrivals area. If you will be using the JR Narita Express to get into Tokyo from the airport you can just do it all at once. If you are using the Keisei Skyliner for the trip into Tokyo, their ticket office is right across the hall. If you will be using the limobus, use the JR office in the Arrivals Hall as that is where the bus stand is located.