If an item isn’t yet available, you may be able to pre-order and then download it when it becomes available. You’ll receive an email the same day it becomes available to let you know when you can download the item.
Pre-order an item: Click the Pre-order button next to the item. When the item is available for download, you receive an email notice. You aren’t charged for the item until you download it.
Download a pre-ordered item: Click the link in the email notice or open iTunes and choose Account > Check for Available Downloads.
View, cancel, or see the expected release dates for pending pre-orders: Choose Account > View My Account, and click Manage Pre-orders.
Some albums or collections you can pre-order include a song that’s available to download immediately. When you pre-order these items, the available song is downloaded and you’re charged only for that song. When you download the rest of the album (after you’re notified it’s available), you’re charged for the rest.