Re: Cheap flights
Aside from Kayak.com which is usually excellent, check which airlines fly into the airport(s) you're looking for (California is kind of large).
Not all airlines list on kayak.com.
In addition, the prices listed on kayak.com are usually net of baggage fees.
For example, united might quote you $200, but they charge $25 bucks for the first bag. Jetblue, on the other hand, has no charge for the first bag, so if their fare were $210 say, it would be better than united's. (and united breaks guitars!)
(Spirit even charges for carry-on bags...and its like $40, so beware).
Southwest supposedly has "get away" deals, if they're on your route, you might want to look into those (I've never done it...so can't tell you) and site like Expedia and Travelocity also tout them, but I've never been able to get one to where I want to go.
(they may be able to alert you on fares to your destination...so look at that if you're flexible.)
Fares also change on a almost daily basis, some people say that Monday is good day to look for fares since airlines are looking to sell a certain number of seats during each week and once they have them booked they raise the prices. My experience is varied, but normally once you're less than two weeks from travel date, its hard to get a good fare.