I have OS X 10.4.11 -- yes, I know! How do I upgrade to it, if I'm asked for 10.5 but it no longer is available. Help!
You have to buy Leopard, and Apple no longer sells it.
Check vendors such as Amazon.
It's not cheap.
10.5 is no longer available. You can try to find it on eBay or Amazon, or you can order 10.6 (Snow Leopard) by calling Apple.
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