Where can I find camping info at the east fork trails to the bride to nowhere?

I am planning to go camping with some friends. I personally want to camp somewhere by the trail to the bridge to nowhere. Can I just start and the trail and just set up camp where ever I want? I also I am planing to taking a fire arm for protection from the wild life if something were to happen. Is it legal to carry it in like a drop leg holster and being unloaded?