You can't. Sorry. If you want to urge Apple to bring that back, you can do so via their feedback page:
though I consider it unlikely since Apple's clear design goal is to remove all such skeuomorphic details.
What is very weird is that my husband updated to IOS 7 when it became available and immediately lost his Wooden Bookshelves, plus his Notes will not launch. No-one at the Apple store can help us. They Reset his iPad Mini, but that did not help...
I, on the other hand, held out and just updated to IOS 7.04 from IOS 6 and I did not lose anything!! I still have my Wooden Bookshelves and my Notes works.
I bought a book on IOS 7 Tricks, Tips and Troubleshooting, and it clearly shows the Wooden Bookshelves in iBooks.
This makes no sense at all !!
iBooks for iOS 7, version 3.2, dropped the wooden-bookshelf look. Any book or web site that shows the wooden look is using an old image from the earlier version. I would guess that you just have not updated to the latest version of iBooks yet but your husband did. If he still has a backup of the older version of iBooks, he may possibly be able to restore that version to iTunes and re-sync that version to his device, but I can't say for certain.
For your husband's problems with Notes, we'd need more details about the problem to able to offer any help with that.