Surprisingly easy to visit from the Bay Area at any time of year... but difficult to get information about visiting, because the area is managed by a mismash of USDA/National Forest Service, private for-profit and non-profit groups, the Army, California State Parks, and who knows who else.

Here are the car-camping options in the area on Forest Service land:

http://www.fs.usda.gov/wps/portal/fsinternet/%21ut/p/c5/04_SB8K8xLLM9MSSzPy8xBz9CP0os3gjAwhwtDDw9_AI8zPwhQoY6IeDdGCqCPOBqwDLG-AAjgb6fh75uan6BdnZaY6OiooA1tkqlQ%21%21/dl3/d3/L2dJQSEvUUt3QS9ZQnZ3LzZfMjAwMDAwMDBBODBPSEhWTjJNMDAwMDAwMDA%21/?navtype=BROWSEBYSUBJECT&cid=stelprdb5312765&navid=091000000000000&pnavid=null&ss=110507&position=Not%20Yet%20Determined.Html&ttype=detail&pname=Los%20Padres%20National%20Forest-%20Home/

If it isn't already obvious from the URL, the USDA has maybe the worst website in recorded history.

Yeah, that is one fugly URL. But a good web reference.