Originally Posted by xDeathsWishx
Uh, good question. Try Google. Since the PSP isn't really skinable (ie. it was not designed to have user-replaceable parts besides the battery), you would have to open it up and manually change the front and back.
Opening the PSP isn't really that big of a problem (just be aware that you can pretty much kiss your warranty goodbye if you do). But I am not sure how hard replacing the front and back parts would be. Since it wasn't meant to be done, it probably involves some soldering. (I have never done it so I could be wrong.)