This first one's for a Macbook, but as they also have an iphone cover an ipad one should be on its way.
Antique book appearance hardcovers.
A selection of classic covers available including these.
A lovely row of aged book spines.
Then take a look at this alternative:
If these are too expensive, or you are crafty, or wanting to make some presents this year, I found a great DIY tutorial of how to make the above one for about $3.