Quick note that if you've done AncestryDNA, they've updated their results again (obviously, your DNA doesn't change, but as more people participate, they're able to identify more specific geography for your ancestry, and moreso, the path your ancestors took to where you are now).
They've ALMOST zeroed in on my genes coming from Waterford, like almost every Newfoundlander whose ancestors came from Ireland.
For example, whoever my ancestors were in 1750, a lot of people also descended from them came here, and a lot stayed behind.