Mostly self-taught, I'm afraid. Lots of good schools around here, but I just don't have the money for the ones I want

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Fonts of Knowledge:
Mr. Green, shotokan karate, Nacogdoches, TX: taught me how to look at martial arts movements and how to learn them mo' better. Also taught me how to punch with my hips, and without hurting my wrists. If you're in that area and you want to train with an ex-military, 60-year old guy in better shape than you, who has a degree in education, I highly recommend.
The Fighter's Notebook: Excellent beginner's source book on the ground game. A lot of it would be better supplemented with some greco-roman wrestling, but that's what my scribbled notes are for

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Mr. Birdsong, aikido, Austin, TX: wonderful, wonderful footwork. Stepping into attacks, walking circles around an opponent, shifting direction with little loss of speed or control. Yummy stuff.
Mike Sigman's Internal Strength videos: If you want a dry, mechanical look at internal strength, this is it. Perfect for learning how to do it, without any of the flash and hype.