Standard Amsterdam hotels bookable through the big engines are poor value. Go for a bed and breakfast or small inn, especially with dollars.
Check TripAdvisor. I would highly recommend the Maes B&B: web: bedandbreakfastamsterdam.com (email: [email protected]). It is a perfect Dutch experience (I lived in the city for 6 years and it was fun to go back to a place like this).
There are similar places like Sunhead of 1617 (www.sunhead.com).
Among cheaper hotels, there is the cool, modern Piet Hein (Vossiusstraat).