First things first! If you are going to be driving anywhere in Nagano in winter, you need a 4 wheel drive vehicle fitted with Snow Tires. In fact, if it is snowing, then there will be police officers standing the the entrances to the expressways checking that all cars have snow tires.
From Tokyo and Narita Airport
There are two main routes from Tokyo to Hakuba. If coming from central Tokyo, or Narita Airport, then the northern route, via the Kanetsu and Joshinetsu Expressways, is quicker. However if coming from Shinjuku, Shibuya, or Yokohama, then the Chuo Expressway is easier
Directions (via Kanetsu and Joshinetsu expressways):
Directions (via Chuo expressway):
From Nagoya and Osaka
There is only 1 real route from Nagoya up to Hakuba. If coming from Osaka then take the Meishin Expressway to Komaki and turn onto the Chuo Expressway.