In terms of activities, Gia Nghia is still something of a black hole.
There are no tours available of the area and no tour guides in town -- they all work in Da Lat. The provincial tourism office can't help travellers -- they're busy developing infrastructure for the future. Local travel agents book tours to elsewhere, nothing local.
Motorbike rentals are not officially available, but as almost everywhere in Vietnam, with some persistence, you can always find someone to loan you their bike for a price. It's a pretty area to explore, with forests and waterfalls within 10km of the town.
You're technically not supposed to leave Gia Nghia district -- we were told by the police that wandering into the other districts, other than to head straight up Route 14 towards Buon Ma Thuot, would result in us being stopped and sent back, or detained and questioned.