@volt, it is important to distinguish between new and possibly not informed users (maybe lacking some skills like Google search) from hostile entities simply trolling here.
The first group is part of the community and has right to be informed. This can be simply a direction to wiki page/right thread/a default answer explaining some issue. In my opinion simple 'use the search' is not enough for a reply (gives bad impression), however it should be added to the actual answer.

The second group should be, let's be frank, fought with. It is not about silencing anyone, it is about keeping some standards for the rest of the community. It is always on the per thread/user basis that it should be decided if it is a 'healthy' complaining or is it simple trolling bringing standards of the forum down.