There is a great article in the NY Times about a Jeremy Lin's rookie autograph sale
It seems a seller on ebay listed a 2010-11 Panini auto card numbered 17/25 (Golden State uniform) and it sold for over $12,000 but the buyer claimed his little son actually put in the bid. So the deal did not go through. The seller relisted 7 days later and the card sold for $4,000. I don't think you could get that anymore.