Yeah, looks like it's gone here in the U.S.. From what this link says, there's an approved newer version, Jadelle, but it's not being distributed. That often means Big Pharma doesn't want to let it come out if other competing contraceptive products, like Nuvaring or some of the new oral contraceptives, are particularly profitable and the new implantable might cut into those profits. This hold-out of an approved, worthy product ought not to be allowed, of course, but it happens all the time.
Norplant - Wikipedia, the free encyclopedia