I personally user this report to monitor users but if you changed the where to the computer name you could do a search based on what you are asking.
For us users can regually change or logon to most computers in the business so its easier to know who the primary user is instead of the last logged on.
SELECT cid.[Name] Computer
,(LO.[Domain] + '\' + LO.[User]) [User]
,LO.[Login Time]
,LO.[Time] [Logout Time]
,CONVERT(decimal(10,2),ROUND((LO.[Duration]/60.0),2)) [Duration In Hours]
,LO.[Duration]
FROM [Altiris_CMDB7].[dbo].[Evt_AeX_Client_LogOn] LO
JOIN Inv_AeX_AC_Identification cid ON cid._ResourceGuid = LO._ResourceGuid
WHERE [User] LIKE '%%LOUSERNAME%%'
AND [LO].[Event] = 'Logoff'
ORDER BY LO.[Login Time] DESC