Cars & Coffee is monthly.... first Saturday of every month at the NC Music Factory near downtown. Lots of variety here from American muscle to Japanese imports to Euros and all the way up to exotics. DEFINITELY worth attending!
And I've never been to it, but a bunch of my friends used to go to Charlotte Cruise Ins. It's on hiatus now because of hoons screwing up sites, but it was every Thursday night and supposed to be making a comeback soon. Mostly imports of various makes there.