Your $300,000 price puts a pretty strong limit on where you can look. Even if you look as far east as Contra Costa County most homes will be out of your price range (only 18 out of about 680 in Contra Costa County)
Marcy's suggestion for Santa Cruz is right on target. With state cutbacks, new housing at the UC, for students, won't be starting soon. Santa Cruz has a significant number of homes for sale in your price range.
There are also a good number of homes further south in Monterey County. Areas dependent upon tourist dollars tend to have wider swings in home prices. Finding an area popular with tourists and buying when the economy is weak can lead to very good appreciation as the economy improves. In Silicon Valley homes have risen significantly this year. Finding a nearby tourist area to benefit this way would be challenging.