Oracle Database Discussions

Hi,
I am asked to review the oracle licenses we have and to document them. How is it done in your places? We are doing it manually, collecting every application's user list and so on... (It is boring, tedious and don't know whether it is accurate)

So I want to know, how is it done in other places? Is there any software to do that? If so please shed some light in that direction to me.

Thanks,