If what you want is a directory of users and a way for them to establish netmeeting sessions with one another:
...you could set up an ILS server. The backbone of MS Netmeeting is an ILS server, a quasi-LDAP server that Netmeeting clients register with to annouce availability and link to a user's current IP so that the call can be established. The easiest way to do this is with MS Site Server which has the ILS functions built in and templates to deploy the directory to an intranet site. There is a free Linux implementation of ILS as well, don't know how well it works.
Of course, since Netmeeting doesn't need the server and will connect directly to an IP address, you could use the Netmeeting ActiveX control and write a web interface from scratch, hardcoding the user/machine IP addresses.
If what you want is a a list of cameras and the ability to remotely select and watch/control the camera feed:
...you could use Axis Camera Explorer (ACE) and Axis webcams. ACE allows to connect to and/or control a unlimited number of Axis webcams or video servers, watch video from the selected source, or capture the feed to a AVI file.