Parks seem to be the most regulated of any place you can go to. You need to check their regulations, usually posted at the trailhead or call. Some places, you will need a wilderness permit, some may cost a little. Funny, in Yosemite, along some popular trails, no camping within four miles of the TH, but if camping along the road, you have to be a mile from the road. They also want you to use existing campsites. If they can't find you, no worry, but you might be impacting an area you are in such as a meadow. Also, alot of city folk come to the mountains and want to have a campfire, something about, that is what camping is about. Depending on the season, they would be illegal due mostly to fire danger. With that said, some locals do stupid stuff, target practice out in the woods during high fire danger, mechanics welding and grinding in an area they haven't wetted down or taken precautions. Areas outside of Parks may be your best bet, such as National Forest land, camping allowed anywhere except on the Tahoe NF. As their signs read, camping and campfires in campgrounds only. Stay off of private property. I would suggest acquiring a map of any areas you want to visit or ask that areas Forest Service if you can camp in a spot you want to visit. Most are real helpful as they want to have the public land used. I have camped a few times where no one has camped before or recently, I just left no trace, even had a fire. I dug down in the dirt a little for a safe spot for it, the next morning, I covered it up. I have been back to that spot to camp, I could not find where my fire had been. I live in a small population county, but within less than two hours to very popular camping/hiking/bping areas, so I can go close to home and see few if any people if I want.

We'll see if you come back, most newbies forget they posted something here.