Bummer, I know how bad you feel, it really sucks when you're excited and waiting for something like that too arrive and you get really disappointed when you open the box and it's not in A1 condition, but from what you've described it certainly doesn't sound like the damage is fatal!! Don't throw it out yet, the foam repairs really easily on this plane with a bit of 5 minute epoxy. I should know, I crashed mine pretty hard on it's maiden flight and shattered the main wing into three pieces along with the prop, prop shaft adaptor, motor shaft, cowling and tail. I thought the world was going to end!! I was sure that I'd totalled it but I just sucked it up and glued it all back together. I covered it in clear packing tape and spent $15.00 to buy a new motor, prop and adaptor. It looked a bit dodgy after gluing it but after the tape went on she looked like new again, it's been flying great ever since, and best of all it's still on the original wing.
Sounds like the damage to yours is more cosmetic than structural. Do you have any pictures?? I can probably give you a few repair tips... Oh, and don't forget to cover it in clear packing tape too, that will give it heaps more structural integrity and make it look better too!! Just patch it up with 5 minute epoxy and apply the tape and I garantee you won't even notice that it was damaged. As far as Art-Tech being cheap, well they are!! ...but you've got to put things into perspective though. You're getting a pretty good 4 channel RTF aileron trainer for $156.00 Even if you do eventually need to replace the wing (Which I doubt) that's only $180.00 total, I know you can spend a lot more than that and end up with something which is not as good as the Cessna 182. You'll eventually discover that the amount of fun and enjoyment you're going to get out of this plane will far out-weigh that cost.
The blame should really be directed towards the Ebay seller for not adequately packaging the product. To be totally fair, on their website
http://www.art-tech.cn/ Art-Tech tell people not to buy their products on Ebay, and also tell sellers not to sell their products on Ebay but if you are willing to the risk then go for it!! It's entirely possible to get a real bargain on Ebay, and it sounds like you did if the damage ends up being as minor as it sounds and totally repairable.
You might even be able to get the seller to send you a new wing if you send him pictures of the damage, if not threaten to leave negative feedback about the transaction. Personally I've had many good transactions on Ebay without a problem.
Brace yourself though, all RC planes crash and sustain some damage eventually so my advice to you is the keep the 5 minute epoxy handy and above all don't worry about it too much!! The plane you picked is a good one and it's probably one of the easiest to repair that I've ever seen. It flies great and has heaps of power to spare so patch her up and enjoy it!!
God Luck!!