Have you thought of using twitter? I know this may sound lame for someone who has never used twitter. I thought the same thing before I started using twitter, the media has given it a pretty bad image. Twitter is actually extremely useful if you use it in a specific way.
If you try twitter, you may not get immediate results but eventually you could get responses from people in your domain that you would not be able to find on any blog. Not every experienced person in "X" can post about "Y". Instead ask a few people what "X" the use for "Y" and you may get some interesting responses. Also, following people in a specific domain, they will talk about new things that they come across. I have found a lot of interesting software through using twitter that I never would have come across before.
If you need some detailed help with how to use twitter you can contact me. Originally I quit twitter when I first started. Then I forced myself to use it a few months later and saw its potential.
If you would like more of my help, I guess the first step would be make a twitter account. Message me there and we can exchange emails. My twitter is twitter.com/espinet.
Matt
Just want to add another comment regarding the previous post. I am following a writer from ReadWrightWeb and he talks about things that he doesn't always post. He also gives additional information about topic "Y" or talks about it even before a post goes up.