Since it's local for me... just about anywhere in the Sierra national forest. Hundreds of places to camp. All within a couple hrs. drive for me. I prefer anywhere primitive near a stream or lake, but sometimes a developed site works, too. Mono Hot springs is one of my favs if it's not too crowded. Spent lots of time there as a kid. Huntington lake has lots of sites. Courtright lake @ the S.E. side of the Dusy/Ershim trail has some cool primitive lake side spots. (if you have a 4x4) Typically, I prefer the higher elevations.
Haven't been up there in years, that place is a playground!
Kern River, Ant Canyon. Thats the only place worth camping. Sand beach on the river. Non developed camp ground so you dont have to deal with other ppl. Fishing is good, and you can camp as close to the river as your dare. It is right of sierra way a few miles past the bait shop.
When I lived in Redding I enjoyed some great hiking trails in the Shasta-trinity area immediately around Wiskeytown lake. The best is to go to Brandy creek and then follow the access roads up the creek from the picnic area towards the Waterfalls... Plenty of camping, swimming, or whatever you want....