Unfortunately Disney tend to operate a system of only putting films on limited release so that they can re-release them (with all the hype that goes with a Disney release) a few years later.
I'm not sure about DVDs but they used to operate an approximate 7 year cycle with VHS videos. Which means it may come out again in about 2009... But who knows.
In the mean time, you may be able to find a copy on eBay.
angbur's right about the Disney rotation thing. The same is in practice for DVDs as well, as only I too well know, as i sell the bloody things and have peole asking every other day for all the oldies! You can get the more up-to-date ones, but for some reason not Beauty & The Beast. Go figure...
That sounds like you do the same job that I did about 10years ago BrainMonkeys.
An old woman once asked me if we had Cinderella in stock. I told her that it probably wouldn't be available again for another 6 years. She replied she would probably be dead by then and promptly left the store, leaving me completely bewildered... Oh the fun I had in them days!