Through the Beurs van Berlage we have been offered the better rooms for the better prices in multiple hotels. Please check the website of the Hotelservice Beurs van Berlage for more information, or to book a room.
For those bringing their own tent, we recommend this overview of Amsterdam campsites.
Airbnb offers an overview of private hosts in Amsterdam. Check out the Airbnb Amsterdam website!
The Amsterdam Tourist Information (VVV) recommends on hotels, hostels, bed & breakfasts, and houseboats. Check their recommendations on where to stay!