[Suzerain of Sheol]

I used to spend a lot of time on TVtropes and Spacebattles. Tons of information on TVtropes in simple to absorb formats, just don't... talk to anyone there. Really. Don't. Spacebattles is one of the biggest sf/fantasy boards iirc, tons of really smart people there who talk about everything under the sun. Just kind of absorb stuff by osmosis. (Lots of really stupid people, too...)

Other than that, lots and lots of reading. I have an entire bookshelf of "research" for the kinds of writing I do, plus I go to university for classical and medieval literature and poetry, so I've gotten a lot from there too. (With some postmodern thrown in for good measure...)

Beyond that... I can honestly recommend Youtube. There are some really good documentaries you can find on this sort of stuff if you have the time to watch them. (I usually game and watch something in the background, while playing another game on my phone, while posting on Tris, while talking on Skype...)

And finally, just reading really good writers can help your actual prose a lot. I look at my stuff from a few years ago, before I read Erikson, Bakker, Donaldson, and others (all fantasy authors), and after, and the difference in quality is striking.

Studying film can help too in learning how to properly (and how NOT to) pace stories, since you can absorb an entire plot in a relatively short amount of time. Learning how to apply the basics to the written format, and then what can be added to enrich it in the available space of a novel, is essential.

Basically, the more knowledge you absorb, the more your imagination can draw on, combining things in new ways to make engaging stories and characters.