Hi Chris and Tammi,
As I have been reading about birding in County Donegal lately, I can suggest several sites, especially for winter birding:
Blanket Nook and Inch Levels (on Lough Swilly not so far from you)
Killybegs, Mountcharles, and Bundoran Cliffs (on Donegal Bay)
Malin Head is a popular migration spot, and Tory Island is supposed to have a good throng of breeding seabirds.
Rocky Point regularly turns up good birds, but I have yet to find out exactly where it is. Please let me know if you do.
-Adam