A Homestead Declaration is not a property tax form, and it is not filed with the Assessor's Office. You may contact a stationery store to purchase this particular form, and, once completed, the County Clerk-Recorder may then accept the document for recordation.
We recommend that you thoroughly familiarize yourself with all current legal aspects and ramifications of homesteading process before filing such a claim.
You may find more information by visiting Declaration of Homestead.