It's out of my specialty; Jim Reily may know. Outfits have been selling lists for a long time; some states, e.g., NY, have some statutory controls. Absent statute it seems to me that the only remedy is a contractual one contending that eBay has breached your contract but that wouldn't get you much more than a nickel and a good cigar. I don't know if the conduct supports a breach of privacy action or not. I'll ask around my shop and see if anyone who teaches this kind of thing has an answer.