Do have a look at my graphical contributions to Wesnoth at Contrib:Commanderkeen, if you are making a campaign I have drawn a few portraits and I plan to add more soon.
I'm currently working on a 6 scenario camapign with a unique twist (well, I haven't seen any campaign like it...). It isn't posted anywhere yet and won't be until I have completed at least the first 3 scenarios, which may take a while.
I occasionally play MP games of Wesnoth and lose *almost* every time.
My main contribution to Wesnoth is drawing portraits (not that I have contributed any to mainline) and finding the occaisional bug (i.e. one!). I am working on drawing better portraits in both the Wesnoth style and a painting style.