The "Official" HM site: http://www.heavymetal.com/
John Findley's Tex Arcana was one of my favorite HM stories. He had it all online, with some edits, but it's been taken off. Fortunately it's still for sale. It's been years since it was updated, it was still really cool: http://www.texarcana.com/
Rod Kierkegaard Jr. did Rock Opera in the 80s, which not everyone liked but I did. He's still writing, his Obama Jones and the Logic Bomb is futuristic and very enjoyable, you should read it. And his other stuff too. His blog hasn't been updated in a few years: http://rodkierkegaard.blogspot.com/ but he's more active on twitter these days: twitter.com/rodkierkegaard
https://heavymetalmagazine.wordpress.com/ Recently migrated to Wordpress. A now-comic-artist putting up a scan a day of HM pages, from his late father's collection, with a critical but appreciative eye.