I was gonna say...I know a BUNCH of video game composers that fit the bill perfectly, but they're not 'bands' per se.
Akira Yamaoka was the first one I'd post, the composer for the Silent Hill games.
Also really great, though in less quantity is Shoji Meguro, the composer for the Shin Megami and Persona games. He is much more electronic/groove oriented, but he also has some really great ambient, slow, brooding tracks as well, you'll just have to search for the ones you like. A lot of piano based tracks. Also, and much more in quantity of the genre you sound like you want, is the Shin Megami Tensei IV soundtrack, especially towards the end. Shoji Meguro didn't compose it, it's actually a few different composers, but it's all up on Youtube (also the soundtrack itself is for sale, I went with that option) to check out and as I said, towards the end of the soundtrack there are a shit ton of awesomely gloomy, ambient, apocalyptic tracks.
As far as actual bands go... The first one that came to mind is Storm Corrosion of Wilson/Akerfeldt collaboration (I almost wrote team-up which sounds so much cooler for men of this caliber).
Other than that...that's about all I've got at the moment. I know how you feel though, and once you've got such a specific sound in your head and want that specific of detail, I think really the only way to find it is to search for it yourself for hours on end through the musical world on the internet.
Topic: Looking for a certain type of dark ambient music (Read 946 times)