Santa Lucia Sportsmen's Assn. in Atascadero doesn't charge range fees after you become a member. Membership is required for rifle & pistol ranges, but not for trap and skeet. Trap and skeet are open to public Weds. evenings and Sun. mornings. Its been a long time since I've shot trap or skeet, so I don't know what the price per round is. Its a nice range, they've done a lot of improvements lately.
They have a decent website with all membership details, etc.