Ouch! Pretty but pricey. For example, check these out:
http://www.ebay.com/itm/4pcs-Lovely-new-Back-Cover-Case-Skin-iphone-4-4th-4G-HC-4-/260898007580?pt=PDA_Accessories&hash=item3cbebbaa1c
Asof this writing, 247,186 iPhone 4/4s cases. For decorative cases I've always bought from eBay, never had a problem from Hong Kong, etc. Just takes a couple weeks.
Not to rain on your parade, but I could never see that kind of money for decorative cases. I buy one top-quality protector (Otterbox, Defender or the like), and the rest come cheapo; so cheap that if they get dirty or show wear I just pitch 'em and go with a fresh one.
Of course, your money, your choice.