Hi Elaine -
I paid 300 GBP for mine. But to be honest, I don't know if that was a good deal or a rip-off! I bought it off a friend at work who used to work for Apple. When trying to agree on a price, we found it quite difficult. As you've discovered, they're so rare they're not even on eBay. We had no idea what the going rate was. I think my friend might have wanted more than 300 for his, but he was keen to sell (as he was moving house), and knew it would be going to a good home and that I wouldn't sell it on for a profit if it turned out that it was worth a lot more. I'd be interested to hear what you'd be asking for yours. I have some friends who are jealous of mine and might be interested. The problem with them is that by today's standards they are so under powered and can't actually do much. I've managed to set mine up on my wireless network and use it to play MP3s streamed from my PowerBook. I can also browse the web on it, but even that seems slow compared to my PB. I hope that helps.
John