Please follow these points. I hope this will help aspirants to start Governance and Public Policy's preparation:

1. Start by reading Mark Bevir's Encyclopedia of Governance. He had given elaborate account of theories and main ideas of governance, make sure you follow css syllabus.
2. Akmal hussain's book 'Power Dynamics' is available from his website.
3. I Niaz's thesis 'The Culture..' is also an excellent book on backdrop and current scenario of governance and public administration in Pakistan. You can download it easily from lums and hec sites.
I would highly recommend Maleeha lodhi's book 'Pakistan: beyond the crisis state' (you will have to buy it, i could not find ebook easily, although youtube videos of her book presentations are available).