1. Ebay is probably the best, you could also try the marketplace of the Japanese Yahoo. Also check out the marketplace of this site frequently because a lot of people tend to sell it here before they want to place it on Ebay.
2. From what i know a standard bundle contains the console, modem, telephone cable, RandnetDD disk and several manuals.
3. I think it all depends on in what condition it is, which edition 64dd you're after, bundled or loose etc. Prices range from $200 to $500.