linking a common unique value across multiple worksheets

Excel 2003 -
Hi all. I have a rather complex operation required and I'm wondering the best way to go about it. (Macros or existing functions)

Background.
We have lots of systems which hold contact detials (telephone system, LDAP, Peoplesoft etc) unfortunately they do not syncronise or they do but there are inconsistancies in the records.

All records have a common unique value which is the persons LDAP uid (username - textfield).

What I am doing is pulling all the data into a spreadsheet, a worksheet per system, and am looking for a way to link the records across the sheets to be able to compare the records.

Initially my first thought was to ensure that a uid is on the same row consistantly across the workbook by using some kind of a loop. Something like below (which doesn't work!)

Sub sortRows()
    'if uid is not the same as on other page, insert blank row above
    Dim i2 As Long, rCount2 As Long
    rCount2 = Cells(Rows.Count, 1).End(xlUp).Row
    For i2 = 2 To rCount2 Step 1
        If Cells(i2, 1) <> Sheets("Sheet2").Cells(i2, 1) Then
            Rows(i2).Select
            Selection.Insert Shift:=xlDown
        End If
    Next
End Sub

Can anyone throw any ideas of how to go about this at me?
If you need anything clarified, I'd be happy to explain further.