When it comes to bidding on your own item, I am sitting on the fence, but here's a prime example of how to get caught out. This is the guy who I sold the Lin Green 23/25 card to, then later asked me for a refund because he may not be able to sell it for the same value he bought it for.
http://www.ebay.com/csc/ranglo211/m.html?LH_Complete=1&rt=nc
As you can see, he has been trying to offload this card for a while, and he has been bidding on his own item obviously. He should have sold it to the guy who offered the $122. The point is, if ebay really cared about stopping shill bidding, activities like this would have been easily caught out.
http://www.ebay.com/csc/ranglo211/m.html?LH_Complete=1&rt=nc
As you can see, he has been trying to offload this card for a while, and he has been bidding on his own item obviously. He should have sold it to the guy who offered the $122. The point is, if ebay really cared about stopping shill bidding, activities like this would have been easily caught out.