Bureau of Labor Statistics: useful information on compensation data gathered by the Bureau of Labor Statistics.
Some BLS sites of interest:
Salary.com
Offers compensation information, salary surveys and reports, as well as SALARY WIZARD, which will compute salaries based on job title and geographic location.
California Employment Development Department
This State agency provides wage data by occupation/industry and by county as well as California labor market information.
California State Salaries from the Sacramento Bee
Search this database for California State employee salaries including civil service, CSU, legislative, and UC system workers. Search by name or agency.