I have used Palm Springs and Thermal, (KTRM), in the past. You prolly will not get permission as a private operator to land at Golf Courses. Most in the LA/SD basin areas have shut down due to noise complaints.
RVDT is correect about VNY although the procedures are published, they do track all flights on radar and if you deviate you will get a nastygram in the mail showing your actual flight path:
VNY Helicopter routes and procedures
VNY Curfew rules