Your e-zine sounds like a great idea, and it seems like you will gain a niche market. From a business standpoint, why not take advertisements from non-audio gear companies to avoid conflicts of interest?
I understand that non-audio businesses might not have an interest in advertising with you, but if you were to do a thorough market research, you might be able to come up with hard data that might be convincing to some of these companies. I'm sure audiophiles have a life and do other things, or have other interests and needs, (stretching...but you get my point). A couple of things I can think of are softwares, beverages, maybe furniture (chair for the sweet-spot), firearms,etc... Ok., maybe not firearms, but there have been times where some of the things that I've bought seem to serve no purpose other than target practice.
Just a suggestion, as I would really like to see something like this take-off. Maybe you can use Audiogoners as a focus group (which I understand you are right now), but with an emphasis on how you can gain advertisments from non-audio gear companies.
Now..., back to reality. What else do I buy besides audio gears?