I ran across this Roman Shade tutorial today that looks really quick & easy. Instead of making the whole shade from scratch (I've tried this and given up) she uses a cheap prepackaged Home Depot Roman shade and shows you how to make it look like it was custom made.
http://www.quackadoodle.com/2009/02/custom-shades-without-custom-price.html
I think I'm going to try this this weekend-- I'll post details when I do!