Ok i'm using something abit different for slightly different reasons to you but:
I have a report that basically does a search for logon and log off times for specific users, how long they were in for and i can then do a filter for the users i'm looking for. You could adjust this and change the search perameters to computer name instead of users or add additional where clauses for the computer set you are looking for.
I then have a query parameter called LOUSERNAME and do a like for that. Using the Like % VARIABLE % means i can search for Dave and it will find all the daves in my company and their details.
If you change the WHERE [User] LIKE '%LOUSERNAME%' to WHERE [User] LIKE '0%' it will search for all usernames that start with a 0 for example and %0% would be all accounts that include a 0 or %0 would be all that end with 0.
In your where clause you can also use "WHERE LENGTH([LO].[USER]) = 7" and it will search for all usernames that have a length of 7 characters for example.
Give it a go and if you need more please say i will see if i can mock up something more appropriate.
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
You would probably want something abit like this:
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 '%dave%'
AND [LO].[Event] = 'Logoff'
AND (cid.[Name] = 'LABCOMPUTER1'
OR cid.[Name] = 'LABCOMPUTER2')
AND LO.[Login Time] Between '2012-10-25 07:00:00' AND '2012-10-25 18:00:00'
ORDER BY LO.[Login Time] DESC