Glad to help! It's been a very long time but that costume sticks with me even today - although it now belongs to my partner as she fills it out much better.
Really, you don't necessarily need to find someone who's done one before, but you do need to have your own needs prepared before shopping around. Know what you're willing to spend and just how movie-accurate you want it, and find someone with experience building bodices and corsets. The skirts are the easy part by comparison, anyone can attach ruffles to a 6-panel skirt. Any commissioner who has worked with high-end fabrics, knows how to fit a multi-seamed bodice over a corset, and has the intelligence and problem-solving skills to stick the dvd in and do the research on the shaping and the trim and details is probably going to be good enough to take on the job even if they've never specifically done a Moulin Rouge movie replica before.
And anyone who tells you they can do it for less than $300 is probably fooling themselves, if not you. The materials on my Nini cost well over $200 alone, and I cheaped out on the bodice trim. That's not even taking labor into account.