I threw out my back once in 05 and have done so annually it seems.
You could go to the chiropractor, but I really didnt care for it, nor did I think going 2-3 times a week for 6 months at $20/visit was very practical for me.
But to tell you what really works for me. lifting the core muscles to strengthen that area up. I threw out my back earlier this year doing deadlifts, I waited two months till it stopped hurting and started doing very light back and ab workouts. I'm to the point now where I can once again do moderately weighted deadlifts.
So if you currently arent injured I would do some ab work, some light lower back lifting, and some trunk twists (these help alot for me).