Property taxes are 1% of the purchase price. In addition to that, home owners pay local assessments, which can vary greatly depending on where in CA you live. One of the highest assessments is usually Mello Roos, which is a 30-year bond that pays for community improvements. You can look up more info at http://www.answers.com/topic/mello-roos
Proposition 13 is what governs California property taxes. It was enacted in 1978. Please see the web reference below for more info regarding Proposition 13.
I hope this helps.