An S-Corp is the way you want to go. What that basically means is that you are incoporated, so your business becomes its own entity. So, as you've heard, if the business gets sued, nothing can be tied to you. Also with the s-corp, your income flows directly into your personal income, which means, no coporate income tax(which is a bunch of liberal crap to begin with). In Florida you need an occupational license. I'm sure you need something like that in California. Look up your local tax collectors office, and ask them. Also, depending on what you are going to be selling, you might want to get a "resellers ID". That way, you can get all of your merchandise tax free, and just charge your customers tax. But if you aren't selling a taxable good(i.e. webpage, hosting, computer repair, custom programming) then, you don't need that. If you need any more information LMK.
-Billy