Re: Live aboard Orange County, CA
Pretty much everything Philzy said above is spot on.
As for looking for a listing for live aboards you could try craigslist. The Log, a bi-weekly paper, may also have listings in its classifieds. Unfortunately, most of those ads are going to be people looking to live aboard, not boat owners looking for tenants.
I've been looking at getting a mooring so have been eyeing the ads and I believe there is one MOORING for rent, you'd have to have your own boat of course and renting moorings is supposed to be breaking rules.
As for the harbor patrol in Newport, it is actually the OC Sheriff that takes on this arduous duty and, yes, they've been know to be overly aggressive at times. I wouldn't base future trips here based on that necessarily. In San Francisco they ticket you if you don't have a current "Obama for Pres" sticker on your car. I still visit, despite having to send in the $300 in "revenues" requested every time.