First, I don't think a stand-alone forum would generate enough traffic.
Second, by putting computer-related resources in the computer forum, rules-related resources in the rules forum, and good random stuff in the general forum, people that are interested in those specialties are more likely to see them. If a week goes by and everything is computer-related, then when someone puts up a good monster-conversion resource up, the non-computer people are more likely to no longer be paying attention.
Third, any subdivision of the forums like that would likely weaken the forum since people can only look at one forum at a time (provided only one EN World dedicated window). That cuts down on potentials for attention for any given thread.
Fourth, we have a couple mechanics--one might be a sticky thread in a couple different forums that would have specific stuff. I don't know if that's a great idea. Another would be utilization of the Archive forum.
But overall, I think the current downloads and links method is the best one. If you find an outside resource, talk to the author of the resource and in the meantime start a thread in the appropriate forum and eventually it will show up in links and downloads.