
Samarinda to Long Ampung (one of the "bigger" villages) with Asahi or Pelita Airlines. Return flights twice a week if weather permits. The planes seat about twenty people flying in, but can only hold about fifteen people flying out due to the short runway in Long Ampung. Not only your luggage is weighed, you are too. According to your weight you are assigned a seat in the aircraft.
The best way to get around is on foot along jungle trails. Good maps are practically non-existent and a lot of the trails just peter out or end at little fields in the middle of the jungle. Be sure to ask if you're still walking in the right direction whenever you meet people along the way. The villages around Long Ampung are reachable within a couple of hours or a day.
Either bring your own or eat what the Dayak eat -- It is a good idea to bring some canned food with you and give this to the people of the place you stay at. They will probably serve it in the evenings with some sweet potatoes or rice, which are both the main staples. If you don't do this, pay them a fair price for what they serve you (some families have a fixed price). You will eat a lot of sweet potatoes and rice.
Pretty much the same as eating. You can bring in some bottles, but they won't last long. You have to drink a lot in this humid environment. The river water should be drinkable as is (never drink stagnant water), but it is probably safer to carry some water purifying pills or a mechanical water purifier.