I used this GREAT tutorial for the basic skirt: http://www.danamadeit.com/2008/07/tutorial-a-simple-skirt.html
and then just added a simple ruffle to the bottom.
This is a great tutorial on how to gather fabric the right way: http://www.danamadeit.com/2011/10/technique-gathering-fabric-the-proper-way-and-the-cheating-way.html
And this is a tutorial on making 7 different ruffles: http://seekatesew.blogspot.com.au/2012/04/ruffle-101-7-ways-to-make-ruffle.html
I can't wait to give the skirt to her for Christmas tomorrow!