I liked Dark•Matter a lot... until I read Delta Green. Then Dark•Matter seemed kinda hoaky in comparison.
However, Dresden Files the RPG sounds like it might be right up your alley. If you want fluff, in addition to the game books, you have what... 13 novels and counting to read too? And they're highly recommended (at least by me.)
If you want modern but not too modern and still definately fantasy, you could check out the Weird Adventures PDF. It's almost all fluff, and has a kind of 30s pulp adventure feel--Indiana Jones in a seocndary fantasy world, if you will. And by that, I mean much more explicitly than something like Eberron.
d20 Modern does have a fair amount of crunch--like any d20 game--but it's all pretty familiar crunch if you played any 3e era game, so you can skim over much of it without having to really delve into it. It doesn't come with a lot of fluff, necessarily, though--rather, it comes with a bunch of modular elements that aren't really full blown settings, but rather just the outline of settings. Only Urban Arcana and Dark•Matter got actual setting books, IIRC. I still like it because it's got stuff to build on, the rules are familiar and easy to use without having to spend a lot of time on them, and heck, they're compatible with D&D stuff if you need even more monsters, magic or whatever--just for the heck of it. In fact, I've taken to using d20 Modern plus d20 Past to represent my preferred feel for fantasy instead of D&D. Because its open content, there's also a fair bit of third party content for it, in the form of settings, adventures and more, which may be what you're looking for.
If you can find a somewhat streamlined version of the GURPS system, it's chock-full of setting books that are mostly fluff too, including many that are modern in feel. The latest version of GURPS Horror was even nominated for a bunch of ENnies, it looks like.