Again, Slow and make sure every note rings out clean and clear. Take the song at half the speed (use speed-altering programs like Pacemaker plugin on Winamp, etc) and make sure you can play it 100% at that speed, then slowly bring it up 5% at a time until its full speed.
Sure, its boring and annoying but if you do this, you can learn ANY song in a matter of weeks/months. I am a professional guitarist (college diploma in Music Arts) and altho I jump around to different instruments more than I should to get "really" good, I know that if I wanted to, I could learn the hardest, fastest songs in weeks with this simple method, regardless of how hard/fast it is, just by the simple rules of playing slow and clean and increasing speed, always to a metronome. I really think ANYONE can learn any song if they know how to practice, the hard part of music is writing your own songs/improvising.
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If you really think about it, Learning guitar/music at a TOP/Professional level is as difficult or even moreso than being a Progamer in Starcraft, the only difference is that anyone can do it and the different talent levels dont matter as much (as music isnt a competition).. But the dedication required to be an absolute top end musician is the same, most of my classmates practice consistently 5 hours a day, and the goal of my college program was that we can be placed in ANY music situation, be it classical, jazz, funk, metal, pop, world music or anything, and be able to keep up with anyone and play anything. Of course, that is more if you want to become a well-rounded musician, most of the bands you listed are an average level of skill, but can't do many other genres. (Much like if you learned just TvZ but ignored TvT or TvP, its still terran but totally different playstyle)
Anyways, You have to decide for yourself if you just want to learn afew songs for fun and to play infront of your friends, or if you want to join a rock band that does only that kind of music, or if you want to become a "musician" able to be put in any situation and dive into the world of "theory" (its not as scary as it sounds, if you can grasp Starcraft at least a B- level, you can probably learn the important parts of theory within months if you try). Obviously the first two choices are attainable, but being a true musician is a never-ending journey and you can NEVER learn everything, it really becomes your life. Even the greats like Miles Davis, John Coltrane, Steve Vai, whoever the top of their era is will tell you they have so much more to learn.