@gabriellosz,
Since the item has been shipped there is no way the delivery address can be changed. If your new address is in the same general area as your old one, try calling USPS customer service, have the tracking number on hand, explain what happened and ask if a hold for pickup can be put in place. If they can do that, then you can go to the P.O. and pick it up.
If you cannot place a hold for pickup. Message your seller tell them what happened and that the P.O. will probably be returning the package, and to check the tracking info for it.
To prevent this from happening again, login to ebay go to your My ebay page locate the Account button and click on it. Under Personal info click on Addresses, (you may be asked to login again manually with your username and password) once you do that you will be returned to the Addresses page. Enter your new address select it as your primary one, and delete the old one.
"THERE IS NO SUCH THING AS FOOLPROOF, BECAUSE FOOLS ARE SO DARNED INGENIOUS!" (unknown)
