Actually a private email to the seller isn't interfering regardless of how badly the seller reacts. Interfering would be emailing other people who were bidding on the auction and telling them the item was overpriced (and thus causing them to stop bidding, or cancel their bids). Or posting the guy's ebay handle and the auction link here on the newsgroup, which ought to be pretty tough to chase down, since it's not very likely the person could be traced from their usenet posting header to their ebay user ID.
Oh yeah, and interfering with an auction, as ebay defines it, is not against the law, just a violation of ebay rules, and can't affect anything but the offender's ebay membership. If the offender isn't an ebay member, guess what.
Andy
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