User Creation Date ...in SAP

Table USR02 is the answer.

USR02-GLTGV (field) is the date from when user is permitted to use the system.
So let suppose if you created the UserID on 01/01/2011  and wants to allow him/her from 03/01/2011 then user creation date would be 01/01/2011 but USR02-GLTGV holds the value 03/01/2011 .

Actually user creation date is USR02-ERDAT.