Though I don't know where you're from, you can get the game for pretty cheap on Amazon. Here's the listing for it actually:
http://www.amazon.com/Shadow-Colossus-Playstation-2/dp/B0009I6S0O/ref=sr_1_1?ie=UTF8&s=videogames&qid=1281571052&sr=8-1
It's a great game totally worth playing. If you've got the funds to spare and can actually use Amazon...totally do it.
As far as Ebay is concerned, a quick search shows pretty much the same buyout bid range for a few of the auctions, around 9-10 bucks USD. So it isn't too expensive.
And no, I don't have a copy there, I'd never sell my copy of that game. I'm just giving a hand to someone with interest in the game.