Hi astral
If you need a bit more detail above what NTA and NPM 11 will give, you could also try LANGuardian. Like NPM 11 it uses deep packet inspection but it also pulls other metadata like file names and URI resource names.
Have a look at it in action at this link which shows the integration with Orion. Click on the fileshare traffic under top applications or click on a domain within the website element.
http://demo2.netfort.com/Orion?AccountID=guest
You can download a 30 day trial and it may provide the answers you are looking for if you don't get anywhere with the suggestions so far
Darragh