I have couple question for you guys ???
Do you pay for your guns in cash or Debit card/CC?
what forums do you have to fill out when buying a gun and what forums are unnecessary?
If you're buying a rifle/shotgun you'll only need a drivers license and fill out a couple forms. And be 18+.
If you're buying a handgun you'll have to take the handgun safety test (takes 5 minutes to do, common sense questions that a 8 year old could answer). Once issued your handgun safety card, you will need a drivers license and another form of residency (any gun store could be more specific with this but I'm pretty sure a DMV registration form or utility bill should work). You'll also need to be 21+ for a handgun.
Read up here: http://oag.ca.gov/firearms/pubfaqs
If you're buying your first weapon I recommend a .22. You'll be able to learn basic fundamentals easy, and plink away cheaply.