My recommendation to you is to visit the BLM (Bureau Of Land Management) office in Barstow CA. http://www.blm.gov/ca/st/en/fo/barstow.html
They have maps in there office that you can purchase and have them personally marked by them as to where to can target shoot on there property. I was there not to long ago and I purchased two large maps for 8$
The only bad thing is that to get to most of these areas, if you do not own a truck or SUV you will not be able to reach these designated areas.
This is what I do. I think it's silly to go to a range and pay a fee to be told what to do, when to do it and how to do it. I totally understand why ranges are ran that way, of course due to safety. I would not want to attend a range were people were allowed to run wild. If you go out into the desert ensuring that you follow your basic firearms safety rules you can have lot's of fun because you can set up your own course of fire.