Let KAYAK do the searching
Based on KAYAK hotel searches, the most popular destination is Siem Reap (95% of total searches to Tonle Sap Lake). The next most popular destinations are Battambang (4%) and Kampong Cham (2%).
KAYAK users have found double rooms in Tonle Sap Lake for as cheap as $9 (Siem Reap) in the last 3 days. The average price is $94.