Download Patch at: http://www.vmware.com/go/downloadpatches/
New: https://my.vmware.com/group/vmware/patch
How to do: http://www.kasraeian.com/2012/03/updating-esxi-5-0-to-esxi-5-0-update-1/
New: http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=2008939