First you need to find security software which will log all these events. There are a few out there. One which comes to mind it Sonar by Awareness Technologies (http://www.awarenesstechnologies.com).
It will log all these events complete with screenshots and scraps of emails, chat sessions etc and copy them to a central server for viewing by the administrator of the system.
Before you can decide on a system you first need to work with your management team and decide what events need to be monitored and then select software which can provide that level of monitoring.
For example, sending an alert when any file is copied accross the network may not be the best alert as any time a user with a roaming profile logs on of off of thier workstation hundreds or thousands of network file copy events will be triggered.