From Tokyo Station the Nagano Bullet Train takes only 1 ½ hours to get to Hakuba Train Station. From the station it is only a 5 minute bus or taxi ride to the village of Happo One.
The Nagano Bullet train is quite expensive; a cheaper option is to catch the Super Azusa Train from Shinjuku Station in Tokyo to Hakuba Station. The scenic trip takes 3 ½ hours.
Going by train is a relaxing way to travel but if you prefer buses they are available from Shinjuku Station, taking around 4 ½ hours weather depending.