Here are some really cool musicians that you may not have heard of. Evelyn Glennie is simply amazing. I've seen her perform once with a symphony and once solo and I have one of her CDs. They are all exciting, high-energy performances. Give a listen and it'll completely change what you think about percussion.
The Yonder Mountain String Band is high-energy, but in a different way. Whereas Evelyn gives you lots to watch and hear, Yonder Mountain stands pretty still; Yet their music blows me away. What an awesome group of musicians. They play lots of original stuff but also do a great rendition of a Pink Floyd song.
Another very talented group of musicians is The Waybacks. I'm most impressed with James Nash on mandolin and Joe Kyle Jr. on Bass. Very impressive.
Hayseed Dixie is lots of fun. My favorite album of theirs is A Hillbilly Tribute to AC/DC.
You may have heard of the Los Lonely Boys by now. They were on Jay Leno recently and have been on Austin City Limits. They have a strong Stevie Ray Vaughn influence.