Reddit mentions of Extreme Metal: Music and Culture on the Edge

Besides all of these lovely quotes from fellow metalheads, another source you could use is this book, which describes the culture surrounding the various forms of extreme metal, which is what most people think of when they think about the negative side of metal. I read it, and while for me it was preaching to the choir, it might be exactly what you're looking for.

I find black metal interesting for a wide variety of reasons. First of all, I am attracted to its sonic aesthetic, like you have been. It's immersive and cathartic, and I think its suited to express a certain set of emotions in a way no other style can. In addition, I think it is a shining example of the post-modern condition. It fits seamlessly into models of modernity from many social theorists. It is the rejection of Lyotard's metanarrative (casting aside "traditional heritage" (music, religion, you name it), expressing distrust for community/national leaders, etc.). It is the result of Durkheim's 'anomie' and an example of Simmel's urban subculture predictions. People all over the world are using this music as a vehicle to express misanthropy, hopelessness, anxiety, hate, and a profound frustration with the modern condition, yet are connecting with one another in carving out this subcultural niche. And it's not all about hate! A lot of black metal is about more than just rejecting or retreating, it's about offering up alternative philosophies/advocating people go decide what matters to them, and stressing personal responsibility.

Beyond that, as with every globalized musical style, space still plays an important role, and it is interesting to note idiosyncrasies. Local/regional folklore plays into black metal a lot, especially with NSBM (not unlike German Volkskunde), and it is interesting to see this co-opted (***note: I'm not an NSBM fan!)

I also just want to study it because it's an opportunity to connect with people who share something with me, however arbitrary what we share may be.

If you're interested, there have been a number of great recent publications on heavy metal. Check out this, this, this, this, this

Edit: grammar

If you're looking for a scholarly/academic take on metal, then you honestly cannot go wrong with Extreme Metal: Music and Culture on the Edge by Keith Kahn-Harris and Heavy Metal: Controversies and Counterculture (Studies in Popular Music). Both are excellent reading, and as they're academic studies can be quite in-depth. Definitely worth a look if you can find them.