#2
easier than what?

Just look at diagrams and memorize them box by box. Start with something easy. Usually the pentatonic, then gradually add more notes, like then the blues, then the natural minor. Then learn how all modes are the same and see how they fit together, so you really only need to learn one. Throw in the melodic and harmonic minor in there too somewhere.
Yeah Dimebag is not the "Greatest Guitarist" of all time... Hendrix maybe... I must go get food to eat with my mouth

$250 for an amp? wow. is it worth it to invest that much in the amp?

#3
Well, learn the shape, learn the theory to understand why the shape is that way... there isn't always a shortcut. To get better at guitar, you sometimes have to sacrafice the fun of just playing tabs.