Here's a video showing a ruffler foot in action on a very old Singer machine. http://www.youtube.com/watch?v=zbG_2sjyOS0 I've seen these sold for as much as $75, but I got mine for $15 and it works on any low-shank machine.
The satin charmeuse and nylon chiffon I got from Murielle Roy & Co. I've been very happy with my service from them and they are happy to send samples prior to ordering. The nylon chiffon (not regular chiffon or tulle that you can find in stores) doesn't fray so it makes it easy to use for all the ruffles. I have yet to find any store in town that carries it, so I have to plan ahead and order it online.
I started with a yellow leotard that I purchased online and added the sleeves to it. The skirt is a separate piece. I made the headband out of leftover satin and just ironed some fusable facing onto it for structure. Then I ironed it with starch several times and attached some elastic to the underside.
The directions I loosely followed for this skirt can be found at the sewmamasew.com forum. I also followed these directions when I made Gwenny's pink pettiskirt.