Sry to say but you cant sell a crown item for crowns. That's why you have to think a lot about what you want to buy with your crowns cause when their gone, their gone forever... OR at least till you...
Panini Crown Royale has not yet been released. Although when it is released (7/14/10), it can be found at online card stores(like dacardworld.com or blowoutcards.com), hobby card stores or online...
You could sell your coins to a coin dealer in your area, or you could try eBay.If you choose to sell on eBay, you will need to be able to describe your coin very accurately, especially the condition...