Are you not seeing them in Event Viewer in the Security Log?
Keep in mind that in Windows 2008 there are a number of additional new logs, but what you want should be in Event Viewer --> Windows Logs --> Security.
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CompTIA A+, Network+, Server+, Security+
MCTS:Windows 7
MCTS:Hyper-V
MCTS:System Center Virtual Machine Manager
MCSE:Security 2003
MCITP:Enterprise Administrator