Sometimes when you buy things in shops, the person will wrap it up for you...what some unscrupulous shop keepers, will pull the ol' switch-a-roo and exchange the product you just paid good money for, sor something of lesser value. Make sure you get what you paid for...and some shops will offer to send the package home for you...if you pick this option, take a couple pictures of the item, to ensure there is a record of the condition of the item in case it gets dameged on the way home threw the post.

CD- Have you ever had a shop mail something for you?

I think I'd worry too much about that. Its not really like you can go back to exchange it.