Oh, GoatSim. If I buy you now, you'd be my second most paid game ever on Steam after I rage bought Witcher 2 a couple of years ago for 15€ or so, and I didn't even had a PC powerful enough to run it at Sajjajja's 640x480.
But if I don't buy you now, will I be able to sleep tonight? Will I be able to look into a mirror? Will I be able to stand the sight of my face?
To my knowledge it's never been reissued and is in the same hell that most non-Star Wars Lucasarts games are in. Best bet is ebay or maybe Amazon marketplace.
In Italy some years ago there was a reissue of Lucas classics on CD (or DVD?). I got Grim Fandango, Sam & Max and some other games I can't remember at the moment, that I had when I was a kid but I lost during the years.
Only problem was the fact that they were the only-Italian version, but those were the times when our translators were totally great.