From Consumer Wiki
Seller's permits are required for anyone engaged in business in California who intends to sell or lease tangible personal property that would ordinarily be subject to sales tax if sold at retail.
The Board of Equalization will send consumers information on rights and responsibilities relative to sales and use tax.
Board of Equalization (BOE)
450 N Street
Sacramento, CA 95814
(916) 324-2926 (Automated)
See also: Business Opportunities