It may be useful to have such an area where frequently requested resources can be placed. Or the same questions that keep repeating are answered. However, it will be necessary to moderate such answers and resources carefully. Otherwise we could end up with misinformation or opportunities for endless advertising thinly veiled as resources.
Agreed with JudyW, Wiki's usually become littered with spam comments! Wikipedia on the other hand uses custom software to deal with this that is in the form of bots, that clear either spam (unintentional or intentional) along with inappropriate content. The software that Wikipedia use is called Mediawiki and is free of charge (open source) I guess this would be an ideal solution here, but would require some modifications to the header so that it fits with the general PT theme ad of course sufficient moderation to remove content as applicable.
There are several Open Source software packages available for wiki's, but Mediawiki given its use by Wikipedia is largely considered the best, for a number of reasons I'll not go into here.
Hope this helps,
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