User type scripts

I am trying to figure out the best way to create a script which checks for new user creation? I am currently using Active Directory for most of my local user accounts to remove the need to keep up with passwords and all that good stuff. But I want to make sure no new accounts are being created and when they do I'd like to be notified or at least send off an email or something to be alerted. Basically, prevent new local accounts from being created. I am not sure if SUSE has something already built-in that can detect and alert on that or if there are open source tools that would be easy to implement.

Another item is the accounts that are present I would like to identify the local accounts that are or have not been used and which accounts have not changed their passwords in the last 12 months.

Any good built-in tools or any good scriptwriters out there able to lend me a hand?

Thanks in advance! Love the distro and the community.