Question
I gave a large natural pond, approxamately 50x100' with average 2'
depth. It has two large Cypress trees and a few fairly large turtles.  I
would like to add some plants and fish. I live in coastal  North
Carolina.  what do you suggest would work best?

Answer
First, let me say that I am so sorry that I was unable to reply to any e-mails yesterday.  We have slow dial-up at home.  It rained and rained.  The underground phone lines were waterlogged.  I was unable to maintain an internet connection long enough to do anything.  So, I had to wait until I got to work where we have fast internet.  The problem is, they expected me to do "real" work and not help you so I was unable to get to your message until now.  

Native plants and animals would be best.  Your local pond club may know more about that.  Here's the URL for a NC pond club (there may be more):
http://www.nckws.com/

As far as marginals go, on my page at http://www.fishpondinfo.com/plants/marginal.htm , I list marginal plants and have a yes in the table for plants that are native to the Eastern USA.  There are too many for me to list here.  There are many native fish native to NC.  You have to decide if you want larger "game" fish or smaller fish or both.  My page on native fish is at http://www.fishpondinfo.com/misc2.htm
There are really many plants and fish from which to choose.  Good luck!