You must file for expungement petition in the county in which you were convicted in. There are 58 counties in California and each county has its own Superior Court.
Listed below are the surrounding Northern California Superior Courts.
Superior Court of California
County of Sierra
100 Courthouse Square
Downieville, CA 95936
(530) 289-3698
Superior Court of California
County of Shasta
1500 Court Street Room 219
Redding, CA 96001
(530) 245-6789
Superior Court of California
County of Sutter
446 Second Street
Yuba City, CA 95991
(530) 822-3306
Superior Court of California
County of Tehema
633 Washington Street
Red Bluff, CA 96080
(530) 527-3563
Superior Court of California
County of Yuba
215 Fifth Street Suite 200
Marysville, CA 95901
(530) 749-7600
Superior Court of California
County of Yolo
725 Court Street
Woodland, CA 95695
(530) 406-6700