These are good resources for buying your archival grade supplies. I frequently use these sources for my clients and myself.
Architecture & Historic Preservation
These are the primary sources for both learning about historic preservation and how to apply for historic designation of your property.
A fairly comprehensive list of California historic preservation organizations big and small:
Historic American Buildings Survey/Historic American Engineering Record (HABS/HAER)
Secretary of the Interiors Standards – Archeology and Historic Preservation:
National Register of Historic Places:
California Register of Historic Places:
Los Angeles Office of Historic Resources (Landmarks and Historic Districts (HPOZ’s):