There is a reason why they built the first Canaima hotel in this location 30+ years ago. Imagine looking directly at waterfalls with table-top mountains behind them as you sip your morning coffee. The location is absolutely stunning. And it is literally across the street from the airstrip.
Note that the name is "campamento" which means, literally, campsite. It is much more than a campsite with clean (though sparsely furnished) room, and a good restaurant. But if you are looking for Club Med, you won't find one at Canaima. Also, please note that all food and beverages need to be flown into this village, so you won't always find your choice of drinks and snacks.
It is part of the government-run Venetur operation, so it may be a bit difficult to get reservations directly. Go through a local travel agent (in Puerto Ordaz or Cuidad Bolivar) to get the reservation, for the room, as well as waterfall tours. On the other hand, being part of Venetur, it means that you don't have to worry about getting over-charged by the hotel.
Service is a bit slow, so don't be in too much of a hurry.