Don't bother. Replacing a keyboard on an iBook is pretty easy, and IIRC, doesn't require any special tools besides a Philips #1 screwdriver. So just hit eBay, look for someone parting out their iBook (make sure it's the same era as yours), and just buy the keyboard.
To replace it, there's two tabs on the top of the keyboard. You just pull those down with your fingernails, and then pull back and the keyboard should lift out. Just be careful because it's attached via a ribbon cable. Once you get it aside, you should see the cable going under a metal plate which is held in by three screws or so. Just remove those screws, and then you should be able to pull the keyboard cable free from the logic board connector. Just repeat the steps in reverse to install the new keyboard.
This assumes it's one of the later iBook G4 models. If it's a G3 model, my directions may well be completely useless. But if you check the ifixit site, you should be able to find instructions, complete with pictures, for taking apart most iBook models. You may even be able to find a keyboard for sale there. It may cost more than you could find on eBay, but significantly less chance of getting the wrong thing or ripped off.
The letters are wearing off of my iBook and the only replacement letters/stickers I've found are for PC's. Anybody found Mac keyboard stickers or others that can be easily modified to fit?![]()

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