First step is to contact who you rodered it from and tell them it is damaged...

If the packaging looks damaged, it's the delivery company's problem, and you dealer will have to arrange for them to pick it up from you. (He should then be able to send you another out right away)

If the outside packaging is NOT damaged, then the fault lies with Great Planes... Still yet, your dealer should take the plane back and replace it... then he can return for credit or replacement.

If the dealer isn't helpful, then you can send the wing Hobby Services with a letter describing the problem... they will NOT just send a wing out without first having the broken one...

Sorry to hear of your wing... hope you get it resolved quickly...