Firstly , The CS6 update will not work on the CS5 software.
Secondly , There is no need to place the order for any update.
You might be talking about the Upgrade from CS5 to CS6 if so , then has your order been processed and how you checked changing your browser and then downlaoading it.
Also , This might help :- http://helpx.adobe.com/creative-suite/kb/find-download-link.html
but if this is not the issue then I would suggest to get in touch with the Adobe support team to get it sorted.
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