How to obtain Mac OS X version 10.5.8?
If you're already running any version of 10.5, run the Software Update pane of System Preferences.
If you're running 10.4.11 or earlier and have an Intel Mac, skip it and order Mac OS X 10.6 by phoning the Apple Store.
If you're running 10.4.11 or earlier and have a G4 or G5 Mac, purchase Mac OS X 10.5 from a source such as Amazon or eBay.
If you're using a G3 Mac, you can't install or run it.
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