First preference is whatever you can catch in the area you are fishing with a castnet. I know its a dying art but it is what the fish there are looking for. Fiddler crabs and sandfleas work well too especially for flounder. Jig from the piers or fish in the first trench from shore.
Second choice would be shrimp or squid (which stays on the hook better).
I live in Atlanta now but one of my brothers is a marine biologist, worked for VIMS and still lives in Williamsburg. I will ask him if he has any suggestions on local spots, But he has far too many boats so he may or may not have any shore based locations.
You might investigate New Quarter Park. It borders Queens Creek and used to have some access to the creek and an older pier - at one time. Its off the parkway closer to Williamsburg - follow the signs for Queens Lake neighborhood.