From Balikpapan there are many buses. It takes 2 hours and it costs 21.000 rupiahs. Alternately a bus from the airport directly to Samarinda will cost 350.000 rupiahs.
There many things you can see around Samarinda
do any less in samarinda if you stay long
by other food and traditional food in market or amplang in surianata next of islamick centre
There are many cheaper hotels in Samarinda
Getting out Samarinda is, given the region, easy.
For buses to Balikpapan it is worth noting, that they leave only when sufficiently full and stop-and-go along the main road until that is achieved - one can thus save a complete trip to the bus terminal by hopping on; taxi/angkot drivers should be able to point out such buses along the way.
Buses to Berau do not seem to exist any longer, probably due to the terrible road conditions. They are replaced by shared taxis (not a tourist-only affair), which take 14-16hrs, though to 24hrs is not unknown in rainy conditions, 250-300kRp per person.
flight to airport temindung by call start or susy air
by private boath from samarinda to pare pare