The Outcasts of Heaven Belt is excellent. It was first published in Analog, in 1978, but it feels a lot more up to date than that. It's about a STL starship crew who have gone to visit what was supposed to be a very rich system, which was lacking an earthlike planet...only to find that the high tech civilization had fallen apart and was, generations later, still in the process of collapsing, and everyone wanted their ship. It has interesting characters and it's quite good.