Need some ambient stuff to listen to while studying, can't be anything overly
distracting and preferably without vocals. College is like 70% reading and
I'd like to have some music for the several hours worth of reading I have
Metal works pretty well when doing Calcular homework though
Check out some post-rock shit, shouldn't be too hard to find on Sputnik, but the basics are Explosions in the Sky, Godspeed You Black Emperor, and Mogwai. The xx is pretty good, they have vocals but they're not too distracting. Sorry I can only rec the most basic stuff, most of what I'm listening too has that dreamy/ambient sound to it, but at it's core it's indie-pop(Some of the vocals are pretty upbeat)
As far as IDM is concerned Ochre is really chill and he doesn't have any vocal samples going on (maybe one or two songs) because if you're like me those things can be distracting as fuck when you're reading. I'd recommend checking out his albums "A Midsummer Nice Dream", "Like Dust of the Balance", "Lemodie" and "National Ignition". You can check out his music here: http://ochre.bandcamp.com/album/a-midsummer-nice-dream
The Bersarin Quartett is a really good mix of classical and IDM.
Aes Dana's "Leylines" album
Autechre's "Incunabula" album
Am-Boy's "Clayton's Hideout" and "Horrible Oracle Blessedness"
As far as instrumental rock or whatever, Grails is my go to study music. "Deep Politics" is a good place to start if you're not already up on their music.
Classical: Arvo Pärt's "Tabula Rasa" is outstanding. Chopin's work is great too. There's too much to list here really.