Hot answers tagged stickers
If the set is a recent release you can call LEGO's customer service and they will send you a replacement. If it is an older, discontinued set, you can find replacement stickers on BrickLink. Here are all the stickers listed: http://www.bricklink.com/catalogList.asp?catType=P&catString=160
Oh, those look sad! Stickers with white designs on them are notorious for peeling/cracking. I have found that the best way to protect stickers like these is to apply a thin layer of clearcoat to them while they are still new. Wait until the clearcoat dries, then apply the sticker to the LEGO set. You can use pretty much any acrylic clearcoat, medium or ...
Unfortunately older stickers are difficult to remove and reapply because the sticky part of the paper tend to rip off and leave a residue on the LEGO element itself. But the fact of the matter is that applying that taking off and re-applying even a new sticker is a challenge and it will almost always be visibly damaged at least a little bit. Your best bet ...
For long-retired products, it may be possible to find scanned images of the stickers online. Then use a high quality color printer to print new decals which you glue to the bricks. The result is not perfect, but often good enough to fool an untrained eye.
You can get replacement stickers on BrickLink. Here is the link to the 8018 stickers: http://www.bricklink.com/catalogItem.asp?P=8018stk01
You occasionally get "extra" stickers, especially in the Police sub-theme of City, where the sheets have both "Police" and "Polizei" variations: Police Plane Sticker Sheet on Peeron
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