Let KAYAK do the searching
Based on KAYAK hotel searches, the most popular destination is Rapid City (65% of total searches to Black Hills). The next most popular destinations are Sturgis (15%) and Box Elder (10%). Searches for hotels in Keystone (10%) are also popular.
KAYAK users have found double rooms in Black Hills for as cheap as $142 (Custer) in the last 3 days. The average price is $313.