How to download CS4 Design Standard?

How can I install creative suite cs4 design standard.

I had to reinstall my macbook and now I want to reinstall my adobe creative suite 4 design standard. The problem is that I can't find a link to download this version. I really need it for my own use. I know it is an older version but I paid for it and I want to be able to use it. I never had a CD/DVD to install. I had to download it online.

can anyone Please help me?