Ozy,
Hunter Ligget can be tough and I don't know what areas you were hunting but for bow hunters down that way the best luck has always been in the "no vehicle access" area...the one they refer to as the "Indians" area.
You can do OK at Lake Sonoma on foot and you can't spend a better day in the field with your bow than out there walking those hills. The terrain is just beautiful and stump shooting opportunities abound. With that said, if you hunt it try hunting out of Liberty Camp Ground. Yes, you can hunt from a boat if you have one but there is a ton of terrain you CANNOT see from a boat. Although the lake is surounded by huge tracts of private land that the hogs use as their refuge during the day there are stragglers that will hole up that you can find. Just walk slow, get down off the ridge tops and use those glasses a lot and you could get lucky.
People underestimate hogs. They are smarter than dogs and absolutely do not tolerate pressure before going completely out of an area and/or turning nocturnal. And although they are a little myopic, allowing you to get right up on them or have them walk into you at times, when they are pressured they get real good at spotting "contour continuity deviations". In other words, they can spot you at a pretty good distance if you look like something that has changed positions on them.
A lot of public land holds Hogs in California but the problem getting to them is from two issues: (1) terrain, they will inhabit the ugliest nastiest terrain (12 foot high thick chamise and blackbrush) you ever saw making in impossible to reach them and/or (2) distance from your camp/vehicle to find them. Many times where they are at they are so far away and in such an ugly mess of a spot that you would literally have to bring your knife and fork to eat them on the spot because you could not pack them all the way back.
All in all they are fun to hunt primarily because they get is out in such beautiful country. Have fun no matter what you do.