The decennial census of religions was released this week. The website shows the participation by county for a number of denominations. There is also a slide show report released to the press.
Adherents as a fraction of the population by county:
The numbers there are pretty low for Hampton Roads. It's certainly not because people here aren't religious. There's a lot of nondenominational or independent churches here - from big screen latte megachurches to small holy roller street corner operations. And those purple and green areas extend all along the southeast coast and into the central Appalachians. For a lot of this map, those low numbers reflect a particular type of religious involvement rather than its absence.