Find an old VideoGame?

When I was Young I played a Game called, 'Where in time is Carmen Sandiego', I really liked that game, and even though its been a really long time, I want to play it again, For old times Sakes. I have Disk, 2. But I can't find Disk 1 anywhere. The game is about Ten years old, So I Doubt ill find it in Wal-mart. I have looked it up on many sites, And the newer version keeps poping up. i want the original Version, Thats the only reason I want the game in the first place. Does anyone have any advise?