Aang:

Yoko Kanno-Kakusei (http://www.youtube.com/watch?v=57eCu9rkOf8)

Alia:

Craig Armstrons-Ruthless Gravity (http://www.youtube.com/watch?v=oK4dY33YwAM)

Chief:

Jeehun Hwang-Mission 7 (Heavy Gear OST) (http://www.youtube.com/watch?v=hGzCfVkxdro&feature=related)

Kang:

Susumu Hirasawa-Forces (instrumental)(Berserk soundtrack) (http://www.youtube.com/watch?v=UW1d2eyEWDE)

Katara:

Yoko Kanno-Turning Spoke (http://www.youtube.com/watch?v=Y4CZ0XcH9xM)
Soul Caliber soundtrack-Destiny Awaits Noone (http://dl1.ffshrine.org/soundtracks/dl/605/c63ba4/Soul%20Calibur%20II%20Original%20Sound%20Track/109_destiny_awaits_no_one.mp3)

Meluly:

Code Geass soundtrack-Stream of Consciousness (http://aigle94.free.fr/phoenix/Animes%20OST/Code%20Geass%20Hangyaku%20no%20Lelouch%20OST%201/04%20-%20Stream%20of%20Consciousness.mp3)

Miku:

Koh Otani-Freebird (Haibane Renmei soundtrack) (http://www.youtube.com/watch?v=SwUE1DkuCXg)

Nanoha and Fate:

Koh Otani-Someday, Lasting Serenade (Haibane Renmei Soundtrack) (http://aigle94.free.fr/phoenix/Animes%20OST/Haibane%20Renmei/Haibane%20Renmei%20-%20%20Original%20Soundtrack%20-%20Hanemone/Someday,%20Lasting,%20Serenade.mp3)

The Nightmare King

The Eurithmics-Room 101 (1984 soundtrack) (http://www.youtube.com/watch?v=5HmYHMPcycw)

Red Snout:

Juno Reactor-Song for Ancestors (http://www.youtube.com/watch?v=0HB2miRgPpY)

Roxie:

Chris Vrenna-Flying on the Wings of Steam (American Mcgee's Alice soundtrack) (http://www.youtube.com/watch?v=ioqSn3f88x8)
Eurithmics-Winston's Diary (1984 soundtrack) (http://www.youtube.com/watch?v=uWxpQN_6Qt8)

Samus:

Daisuke Ishiwatari-Holy Orders (Be Just or Be Dead) (Guilty Gear soundtrack) (http://www.youtube.com/watch?v=rGetImTgyFA)

Slobo:
Apocalyptica-Grace (http://www.youtube.com/watch?v=hk1sMJ1PXhA)

Tess:

I couldn't help it (http://www.youtube.com/watch?v=RBWgjLN31QY)