Limit Users by Site, Not Time

I am looking for a cost efficient (read: free) way to limit a certain group of users to only a few domains that they can visit on the web.

I’ve given our video department internet access so they can search for release dates, correct titles, movies and actor has been in and out of print tapes. Adult sites are stopped via our main filter, however other people on the network need to access other sites and our current monitoring software only blocks the whole network for specified content. I want to set up a user who everything is blocked except about 3 domains.

Any help would be appreciated.

Bryan James
Cowboy7704@centurytel.net
(please put tech republic in any subject line so my mail filter doesn’t eat any relpies)