There used to be a couple of good ones towards Pittsburg/Antioch, but they both closed down recently, so now it's mostly just Phoenix Games in this area for retro gaming needs.
You can also try Half Price Books in Concord, as they will have some retro games. While the selection isn't huge, but there may be a thing here and there that might be of interest.
If you want some recommendations for a Japan hobby/figures shop, you can Toyslogic in Concord as well, and have a decent selection, albeit, not a typical storefront, and the set-up is similar to like shopping at a very large store front at a convention, but with larger stock of things. Kind of neat if you're interested in that stuff.