Yes, but the well-known ones tend to fill up regularly since, well, they are well-known--and they certainly don't need any more publicity. And, the Rim Fire has impacted many of the nicer dispersed sites--either due to downed trees, still-standing dead trees ("widow makers"
, or current logging/cleanup operations. What we ended up doing is spending an afternoon driving around the NF roads and waypointing places that looked good for camping (and no, I'm not sharing my list, which is pre-Rim Fire anyway). The reality is almost all of the NF roads have places where you can pull over and sleep in a car/van/SUV for the night. Finding a place for a large tent can be a challenge, and unfortunately these places tend to end up with a large fire ring, charcoal everywhere, and burnt cans and broken bottles right in the middle of the only place you could put a tent...
The Gaia mobile mapping app has a property boundary layer that is useful to make sure you are camping on public lands and not a private inholding.