Amazon Warehouse items appear in the 'available from other sellers' or 'available from these sellers' links on the product page of any item [can be books/dvd/cameras/anything that someone has bought through Amazon directly and then returned.]
Look over to the right of the page. Usually there is a box with other sellers.
Amazon calls this 3rd party seller list "The Marketplace" and unlike Amazon itself [above £9 spend], there are charges for postage, even from their own 'Warehouse'. Marketplace sellers have feedback scores, like eBay. Warehouse stuff is bomb-proof because it is Amazon's back door. Other sellers must be appraised as to their trustworthyness. Check their feedback, as per eBay.
Sam NC10s will crop up on The Marketplace all the time. There is a good German seller called Avides. They usually charge £0 p/p and can be trusted 100%. They sell returns from the general retail market, often just because a box has been opened. I've had a Sony DVD recorder from them, no probs.
Don't forget two important Laws. 1] The Sale of Goods Act says that a product must be 'fit for purpose'. If it is duff or it does not fit the specs you stated to the seller [you must be absolutely clear on this and have proof of what you specified], come what may, you must receive a replacement or a refund, depending on the circumstances. 2] The Distance Selling Act allows you to send anything back if you decide you don't want it. I think the 'cooling off' period is 14 days. Generally, the item must be in its sealed package and unlike Sale of Goods Act returns, you don't get a refund of the costs of returning it.
I just registered my NC10 on Sam's site. Despite it having been pre-owned, the registration went through.