The 4 books in my library that (IMO) will yield the most useful knowledge for beginners, in no particular order are:
"Botany for Bonsai" ~ Enrique Castano de la Serna
"Bonsai - It's Art, Science, History, and Philosophy" ~ Deborah Koreshoff (out of print - buy used) has great line drawings
"Bonsai" out of print - a Sunset book - ISBN0-376-03046-1 - buy used, great overview
"Bonsai Techniques I and Bonsai Techniques II" ~ John Naka (out of print - buy new [if you can find] or used) great for design inspiration
Al
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Jumping off point for literature regarding bonsai
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