During the winter, a shuttle bus service typically runs from December 16th to March 14th. Below are some useful websites and apps.
https://hakubavalley.busyohou....
https://hakubavalley.busyohou....
From this winter season, 2024/25, Uber will be available for all of the Hakuba Valley. You cannot Uber to Nagano City yet, but that will probably come next year.