No corkage/BYO legally permitted in the area. We do manage some BYO at offlines, but only because some of our members have "connections" at certain restaurants. It's a BYO wasteland here, unfortunately.
As far as restaurants are concerned, I'm sure that Festiva, irwin and cometspider may have some suggestions. This is more their neck of the woods than mine.
I've had several good meals at Tersiguels in Ellicott City, not far from Columbia. Their wine list is decent.
For small plates and a decent and eclectic wine list and good selection of wines by the glass try The Iron Bridge Wine Company.