Fuck Windows Media Player.
A while back, I used Audacity to rip my LP of Billy Joel's the Stranger to mp3 so I could listen to it on my Blackberry.
More recently, I noticed that a few of the tracks weren't on the album.
Today, I discovered the source of the problem: Windows Media Player ~helpfully downloaded updated track information for this album, including numbering half the tracks as Track 4. It then overwrote the file information on my hard disk with these new details.
Because it saw a number of "Track 4"s, it also did me the favour of removing the extras from my library. And apparently the default setting is to automatically delete files from my hard drive when deleted from my library.
Now that I've disabled those settings, I'm hoping that I will have the original on my backup drive at home. If not, at least I still have the LP and I can rip it again.