Thomas Baxter's book covers the methods and history of this much sought after effect, 'A Card Merely Thought Of''.  It has to be one of the strongest effects in magic, a piece of pure mind reading, the spectator doesn't take choose a card, doesn't look at a card, they merely think of a card - it's the magician's job to find that card.  Just imagine the situation, the card is not chosen, it's not cut to, not selected in any way - that's the situation you have with this effect and that's what this book is focussed on achieving.