How Do I Book A Inexpensive Hotel Room for a Family of 4 In Singapore, Singapore?

I went to Asia Travel.com, Priceline, Orbitz, Hotels.com, Agoda, Hotel club. com etc. trying to book a reasonably priced hotel room for my wife and i and two children ages 12 and 14. All these WEB sites would either only book a hotel room for 2 people or if I marked 4 people it stated all rooms were unavailable expect 1 extremely expensive hotel. I am trying to make hotel reservation for early 2012. This failure of these WEB sites to accommodate families is ridiculous. I tried emailing say Asia Travel.com but they do not list a email contact in their WEB site.