You should not be breeding your dog unless you really know what you are doing. There are, literally, millions of unwanted dogs in this country that need homes. Please don't contribute to this problem.
That said, you probably do not need a license but you should be aware that California has some of the toughest "puppy lemon laws" in the country. http://dogplay.com/Breeding/lemonlaw.html
You don't need a license, and you're wise to want to ensure that your dog's puppies end up in good homes, but you do need to be aware of the responsibility and potential liability you face for selling someone a "lemon" puppy - please see the link below.
You also need to cognizant of the massive dog overpopulation problem in this country, and get your dog spayed so as not to contribute to the problem anymore in the future.
Disclaimer: Please note that this answer does not constitute legal advice, and should not be relied on, since each state has different laws, each situation is fact specific, and it is impossible to evaluate a legal problem without a comprehensive consultation and review of all the facts and documents at issue. This answer does not create an attorney-client relationship.