Hi everyone, I just noticed this thread a little late but thought I'd answer a question. As for Chabot IDPA matches, they do take new shooters and one doesn't have to be a member of the club to participate. Additionally, I believe they will let you shoot with a non-approved handgun or holster/mag pouch combination if you are new, but I believe your score won't be posted at the website - http://www.sfbay-idpa.com.
We like to know that a shooter has either participated in PPC/IPSC or taken a handgun class from a recognized trainer where holster work and safety is taught. At the window when paying new shooters are expected to notify the personnel, and then simply listen to a 5 min (est) instructive speech by one of the experienced participants before the match. The club very much welcomes new shooters, though we are serious about safety. We have around an est. 20-60 shooters show up, with the most usually during nice weather and the 3 times a yr. we do the classifier (June 16th, and Oct 20 left this yr.) We have a great group of people participating, and some very inventive, and (lately) prop intensive stages. IDPA at Chabot is every 3rd Sat of the month. 3-gun, which has some of the same people participating, is every 1st and 5th Sun of the month.