California is very decentralized in a lot of ways and my impression is that their preparedness varies greatly from city to city.
And you have to keep in mind a lot of these realistic earthquake scenarios make Katrina look like a joke.
For example, the Hayward Fault earthquake scenario:
http://www.eastbayexpress.com/issues/2005-02-23/news/feature_1.html
Isn't some pie-in-the-sky 1 in 100,000 chance of happening in our lifeftimes fantasy scenario like a Supervolcanic eruption of Yellowstone; it's something that probably has at least an even chance of happening in the lifetimes of the people reading this thread.
Regarding resources, after one of these earthquake insurance will not exist in California unless it's subsidized federally by people elsewhere in the country. Eventually (after another couple hurricanes and maybe a couple quakes) people are going to take a real hard look at the economics of that.
Eventually due to the mobility of the population and economy I think you'll see a "bounce back' of people moving out of California AND places like South Florida as insurance becomes unavaliable against disaster in those places except for the exceedingly rich.
Interesting, and a good heads up
In a way, I am actually looking forward to it. My plan is to make a career change to becoming a land barron. Seriously.