Currently Being ModeratedOct 17, 2013 7:10 AM (in response to Libee7)
You shouldn't be billed multiple times for a preorder iBook as you are able to download this type of media again free of charge via the steps below. The iTunes Store will prompt you with an indicator that the item has already been purchased and available for download which should prevent you from being overcharged.
In regard to preorders and to see what is pending, I would check out the sections labeled Downloading a pre-ordered item and To view, cancel, or see the expected release dates for your pending pre-orders of the article below.
Hope this helps,