Given that your location is Southern California, I'll tell you that my novella (Fair), which I finished this year, is set in L.A. I live around Toronto. I've been to L.A. a couple of times as a tourist, but as I started to write Fair I started my research with Google which took me to a variety of links. I used on-line photos and comments from people on those photos; I used articles from the LA Times; I used wiki; I used Google Maps. All of this research didn't change my story, but it enriched the story in that it lead me to include aspects of LA that related to my protagonist. A couple of small examples: I refrerenced the Griffith Park fire in 2007; Jurrasic Museum on Venice Blvd; Rosedale Cemetery.
The old axiom of "write what you know" has always made me smile: what is it that we know? The more you research, the more you learn, the more you know. All I would say is that, as an earlier post commented on regarding the use of 18th century newspapers: there is no excuse for not getting those details right. It can be hard work, at times, but you can get a hold of artifacts like 18th century newspapers and use that understanding to "get it right". Particularly now with on-line research so readily available.
Laziness, intellectual or physical, is the enemy of good writing.