I don't know if you have access to this info if you're not a forum member. Try the link and see what happens: http://www.outerbanksflyfishing.com/forum/viewtopic.php?f=23&t=41
If you can't see it, sign up for the board. It's everything you've ever wanted to know about OBX fly fishing, and then some. Also, do a search of the forum here on PAFF. OBX fly fishing has been discussed numerous times in the past.
For fishing streamers, like anywhere else, a sink tip or intermediate line works best. The sounds can be shallow and a floating line may work in places, but overall, at least an intermediate line is your best choice. Not to mention, if you try the surf you'll have better luck with an INT line. I've caught flounder from the surf on the exact fly Sandfly mentioned. Black/orange/red/gold flash Clousers are "money" for some reason down there and they work wonders.
Check out that forum and also do a search here. Lots of good info out there!