Looking for Leopard 10.5 download for my MBA 2009

[edenbensal]

Hello,
I have MacBook Air Mid 2009 1.86 Ghz on Mavericks.
I want to downgrade to the original mac os x that came with the mac and this is Leopard.
Where I can find download of Leopard? How do I install the operating system? Can I install it via USB drive?

 

[blueroom]

You might be able to buy a Leopard USB installer on eBay.