[CentOS] how to find last updates for Centos 5.3?

On Mon, 7 Dec 2009, Alan McKay wrote:

>> I wish I had access to a Centos update folder AS IT EXISTED before
>> Centos 5.4 was released.  The last update set that applied to 5.3,in
>> other words.
>
> Crap, I just removed one with no backups.

and 1) as it was partially inconsistent with upstream, and 
prior practice, as some items were pushed 'early' compared to 
prior release processes, and
     2) since vault.centos.org  has all, with datestamps to 
permit building any particular point in time variant,

... this is important just how?

-- Russ herrold