I want to start learning musical theory and all that jazz. Usually, I just play songs I know, and I find it being very unproductive. I'd like to get playing more difficult things. What're some exercises I could learn to improve my dexterity, hand/finger strength, accuracy, etc. Also, what're some good warm-ups to get my hands/fingers ready for my practice routine (whatever it may be). I'm looking for a practice routine basically. I'm starting to learn scales, although I haven't been trying them that long, so I have made little to no progress with those. What are some metal scales that would be good for me to learn? What're some other techniques that are essential if I ever want to 'be something' as a guitarist? I also would like to learn about chords (what their names are) and keys, and everything else. Basically everything you would learn in a musical theory class, I would like to learn it. I want to become a more versatile guitar player.
well for starters, this site is has TOO MUCH lessons and articles about exercises, warm ups and such, just search and find (go to "lessons" tab and go to "Basics").
about musical theory I can tell you that you Will need it if it's of your aspiration to become professional, although learning it all or all the scales and modes in one time is unlikely, its just too much, so its better you spread the topics over several months or learn theory for a half an hour daily.
for techniques, you'll have to pick them up from learning songs, just browse through tabs and try to study and practice songs who you'll think you'll be able to learn.
if you are clueless about what songs you should approach, there is a beginner songs thread in the Tab forum.
practice at least 2 hours a day!
use a metronome!
learn what you love, so your technique will be suited to what you want to play!
I myself reccomend John Petrucci's "Rock Discipline." A friend gave me a copy of the video and tab book he downloaded from LimeWire (yes, illegally).
His warm up exercises alone can greatly benefit your technique. He gets into other stuff like picking, hammering, legato, etc.
It's quite a challenge...give it a try!!