I've been working on singing a lot lately and I enjoy it a lot as well. I mostly sing along to Tool. That's the sound I like and the only singer that appeals to me. The thing is, Maynard gets some really high notes/pitches sometime which I find hard to get. My question is this, is there are way to increase my pitch/note capability? If so, how?

Also what are some good vocal exercises that I can do to better my voice and make it sound more like Maynard's? Thanks in advance.
Just practice, really. Plus, if you sing as loud as you possibly can, you can widen your range quite a lot without cutting out on the high and low pitches.
Patterns In The Ivy present ethnicity on an intriguing and dedicated level. ~Ambient Exotica
A mesmeric melange of yearning voice, delicate piano and carefully chosen samples. ~Lost Voices