I got mine from Relive the Magic which has its own web site and I originally saw the ad on Lou Mongello's Disney Trivia site (although I think if he knew of all the problems he might not be endorsing them...).
There have been a few threads about this company and their DVDs here on the DIS. I ordered mine the day after Christmas at a deep discount over the original price. Long story short, I got the run-around for well over a month. The last e-mail they sent me said something to the effect of "There is a good possibility these DVDs will no longer be available in the near future, so at least you will have a set!" That did NOT help my mood...

I got promise after promise of when they would ship. They finally arrived sometime around the 2nd week of February (remember, I ordered Dec. 26!!). Since reading other people's experience here on the DIS, it seems like this is just how they do business, and taking forever to ship is standard fare and really has nothing to do with holidays or recent discounts. Like the other poster said, how are you out of stock on something you manufacture youself??? Behind on orders I understand, but "out" of something and unable to even take the order? Maybe they are on the verge of disappearing (no great loss!).
And many of my DVDs skip....
I could request another copy (well, in theory) but I was so unhappy with the company that I just didn't want to deal with them anymore. When they do skip I just restart whatever ride I'm watching. Annoying but at least it's not every time.
Save your money and get the "real" sets from Disney!