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Do you still have the original discs that came with your machine? Disk 2 should have the iLife apps on it. If not, at this point your best bet may be to find a copy of the iLife '11 (or earlier) disc on eBay/Amazon/Craigslist/etc. Also try what Badrottie suggested, just don't be surprised if they try and get you to upgrade to a newer machine.
 
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