SELECT dbo.tblComputers.Computername, dbo.tblComputers.Domain, dbo.tblComputers.LastknownIP, dbo.tblADComputers.OU,
dbo.tblADComputers.Lastchanged
FROM dbo.tblADComputers INNER JOIN
dbo.tblComputers ON dbo.tblADComputers.Computername = dbo.tblComputers.Computername
WHERE (dbo.tblADComputers.OU = 'ou you want')