Probably the best individual book you could purchase is "INSIDE LIGHTWAVE", edited by Dan Ablan.
For an incredible FREE trove of clear video presentations, check out William "Proton" Vaughn's 24 hours of Lightwave training videos at:
http://www.newtek.com/lightwave/24hours_training.php
Also, a hotbed of LW discussion is available at the NewTek site, and at the independant SpinQuad site.
http://www.spinquad.com/forums/index.php
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"Putting the HARM in 'harmonica' since 2005."
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