Tom Fischer from Celtic Frost/Triptykon has written a couple of books. I have Only Death is Real (written with assistance from Martin Ain) and it's fantastic.
The only records I'm looking forward to so far (metal-wise anyway) are Nevertanezra and Leviathan. Everything Burzum has done after Fallen is terrible and nobody else I particularly care about has come up so far.
Just to weigh in I actually do prefer Varg based on his music and the fact that he's a charming little nazi idiot, compared to Euronymous who was just kind of weird.
Tom Fischer's book, Only Death is Real, is fantastic. I also really enjoyed Swedish Death Metal, if you're a fan of that scene you've gotta check that book out. I thought Dani Filth's book was kinda fun as well.
No problem. Tool and Mastodon are both inspired by Melvins as you said, and of those two Mastodon's earlier stuff definitely fits into sludge. Honestly not many bands sound quite like Melvins though. If you like Mastodon you might like Baroness or High on Fire.
Oh yeah, that's completely fine.
For those of you who haven't checked this out yet, you should go download Temple of Void - Of Terror and the Supernatural. Some pretty enjoyable doom/death.