Peter Jalesh 
Introduction to Zen [EPUB ebook] 
Zen Handbook: Zen aphorisms, Zen essays, No-mind Zen

If you are a monk this book is not for you. If you’re a layman you could start your Zen experience of emptiness from a variation of Wittgenstein’s utterance about the world:
“The world of Zen is both, what the world is and what the world is not”.
If you also succeeded to erase the above duality you’d discover another way of knowing; you’d be able to “see” a world that lies within the real world and yet beyond discrimination – a permanent and unified universe – the Emptiness.