In central CA you should look at Parkfield, Ca. That is probably dead center and is known as an area for pig hunting. Pay attention to the size of the ranch though since a lot of those ranches are small and may not really "hold" many hogs on their property, the hogs may be coming from adjacent larger ranches. Rifle and archery allowed down there from what I have been told. In the central valley try looking up a youtube page called "the community show", this guy manages hog hunts on a series of ranches that appear to hold a good number of hogs. Appears to be all bowhunting but that should work for you. Good luck