The Wing Commander IV DVD can be a bit of a pain to find. It was only ever available bundled with a particular type of DVD-ROM upgrade kit, circa 1997-98. If you want the physical disc, it's going to be a wait-until-one-shows-up scenario... but they're not rare enough that that *won't* happen. Be sure to also search for "Creative Labs DXR2"--often times you can find the DVD-ROM that includes the Wing 4 DVD for cheaper than just the game itself.
The other thing you can do is just buy the CD-ROM version and upgrade it. We have a (large) patch that adds in the higher resolution videos available at wcnews.com. There may be an even more seemless way to do this in a month or so, but it'll cost you $5.99, wink wink.