There is an ebay shipping hub in Illinois and I've heard that there is one in California although I can't confirm the one in Cali. If there is one there, I don't know if packages will automatically be directed to the closest one to the seller or if it will depend on the country it will be going to. Basically you ship it to whichever address they give you.
If you are not using ebay international shipping but still shipped internationally then you would ship the item directly to the buyer.
