Find how to's?

Actually, forums like this one are an excellent place to get input on decisions you're facing. I've had some very useful conversations with colleagues that started in this forum and have continued beyond that as we've discovered special areas of expertise and experience in one another. The best discussions have started from a specific question or description of a situation to which someone was seeking a solution. As with any situation involving opinions, you have to separate out the wheat from the chaff but that becomes easier as time goes on.

You can also use newsgroups and mailing lists to keep track of issues of special interest. When you read a posting from someone who seems to genuinely qualify as an expert in a particular thing, make a note of it and look for other things they've written.
If they invite direct inquiry, do so.

But beyond that, one person supporting 100 geographically dispersed users is spread very, very thin so there may be a role for a paid consultantor two along the way. Particularly with security issues, the inherant lack of accountability that goes along with free advice is often not a good thing.

To start with, I would encourage you to pick an issue, do a specific posting with a specificissue and see what kind of response you get. If an apparent expert bubbles to the surface, see what their terms would be to take the discussion off-line and maybe even finish the conversation by telephone.

regards!

paul