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Wirelessly posted (iPhone 3GS: Mozilla/5.0 (iPhone; U; CPU iPhone OS 4_3_5 like Mac OS X; en-us) AppleWebKit/533.17.9 (KHTML, like Gecko) Version/5.0.2 Mobile/8L1 Safari/6533.18.5)

You answered your own question. You need 10.6 to get the Mac App Store.
 
The app store is part of 10.6, that's just how the app store works, so you can't get it unless you upgrade
 
This is actually an interesting question because the iWork system requirements state that it works on 10.4 and 10.5 too. Is it possible to copy the already-downloaded apps from a newer machine over to the 10.5 system?
 
Nermal,

That is what I am wanting to know. Does anyone know how to do this?

Just copy the App(s) from your newer Mac to a thumb drive or CD/DVD, or over a LAN share, etc... and then paste it onto the older Mac, in the Applications folder of course.
 
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