Let KAYAK do the searching
Based on KAYAK hotel searches, the most popular destination is Hakuba (71% of total searches to Nagano Prefecture). The next most popular destinations are Nozawa Onsen (14%) and Nagano (8%). Searches for hotels in Yamanouchi (7%) are also popular.
KAYAK users have found double rooms in Nagano Prefecture for as cheap as $73 (Suwa) in the last 3 days. The average price is $343.