pre-order

I don't know about pre-book, although It seems to simply mean book in advance (i.e. before you usually would or is necessary). Pre-order is easy enough - it means to order something before it becomes available and have it reserved for you. This is from Wikipedia:

"A pre-order is an order placed for an item which has not yet been released. The idea for pre-orders came when people found it hard to get popular items in stores due to their popularity. Companies were then given the idea to allow people to reserve their own personal copy, before the release, which has been a huge success. Pre-orders allow consumers to guarantee immediate shipment on release, manufacturers can gauge how much demand there will be and hence how large initial production runs should be, and sellers can be assured of minimum sales. Additionally, high pre-order rates can be used to further increase sales."

This was published a few days after the release of the PS4 - "day one PS4 pre-orders sold out months ago"

If you simply said order, you'd need to add something like pre-release or pre-publication or advance, so I don't really see a problem with pre-order. No doubt it's being seen more because the Internet makes it easier to do.

But it does look as though some companies use it simply instead of 'order'.