Rajesh Balasubramanian, Director at 2IIM has published a book on CAT preparation titled "Quantitative Aptitude for CAT". The book was published in 2013 by Access Publishing and gives a complete overview of the Quant portions in CAT.
The idea behind the book is very similar to the teaching philosophy at 2IIM, with a heavy focus on thought processes rather than on shortcuts or formulae.
The book can be purchased at Flipkart Click Here