[Not a lawyer, but have paid enough to lawyers that I'll never do that again]
Go to your local library and check out Quicken Willmaker. They publish an update every year, and it's good in all 50 states. You can read all you want from the book, or use the included CD-ROM / software to generate a 'last will and testament' document.
If that's all you need, the task can be completed in around 20 minutes. The book answers most of your questions, and they used to be located in the Emeryville area (NoloPress), so I'm sure they 'get' all the CA rules.
All the best!