Chiropractors, in my experience, have been nothing but "Oh, hey, we can fix that misaligned vertebrae in five more visits!" Five visits later, "I'm not liking the way you're standing, I think *insert medical mumbo-jumbo here* is out of alignment now, let's schedule you for another visit." And so it goes.
Orthopedic doctors are your best bet. BUT talk to your regular doctor, he or she might think it's something else entirely. Back problems come from many places, and not always the back. Sometimes it's something simple like your feet, or it could be kidneys or a whole host of other things.