Check Assembly Weekly History or Senate Weekly History. These sources are organized by bill number. They also cover resolutions and proposed Constitutional amendments.
A separate Legislative Index and a Table of [Code] Sections Affected are also available.
(The current year's versions of these resources are in the Reserve Book Room. Ask at the Circulation Desk. Earlier versions are in pamphlet boxes on range 117B in the California Collection.)
Call the Legislative Bill Room at 916-445-2323 with the bill number in question.