Are there any cases to make my iPhone 3GS look like an iPhone 4?

Are there any cases to make my iPhone 3GS look like an iPhone 4?

No… You don't need to make it look like an iphone 4. Enjoy what you have

You can have a try this one http://www.onecase.co.uk/paul-smith-hard-case-for-iphone-3g-3gs-sea.html or http://www.onecase.co.uk/cath-kidston-case-for-iphone-3g-3gs-flower-green.html