Let KAYAK do the searching
Based on KAYAK hotel searches, the most popular destination is Auckland (57% of total searches to North Island). The next most popular destinations are Wellington (21%) and Rotorua (14%). Searches for hotels in Taupo (9%) are also popular.
KAYAK users have found double rooms in North Island for as cheap as $31 (Rotorua) in the last 3 days. The average price is $199.