DirSpy allows you to see all those using network files within a specific directory. Other impressive features of DirSpy include extensive server/client information, volume information, volume disk space monitoring, directory information, deleted file information, the ability to salvage and purge deleted files, tree diagram of network, see who is online for a particular server, see the connected/disconnected servers for the current user, send messages to users, clear connections of users, query the network for user names, change user passwords and much much more!

DirSpy is the Shareware version. The full version can be purchased by clicking on the "CLICK HERE TO ORDER" button below for around  29.95USD.