Brother, I have appeared in CSS 2013, CSS 2015 but unfortunately could not qualify. As far as Fpsc General Recruitment is concerned my css preparation has helped a great deal in qualifying for the said posts so cannot be summarized by naming only few books.
But to answer your query I'm naming some sources of information I have gone through Caravan GK MCQs book, EDS MCQs Mian Shafiq, EDS MCQs Imtiaz Shaid, Islamiat MCQs Tahir Bano, PA MCQs Sohail Bhatti, Maths Prep from Matric level books, CA from Newspaper, CSS Past papers, Csspoint pdfs and online MCQs websites. are some places where i invested my time and Al'Hamdulillah I have qualified fpsc test consecutive 8 times.
But above all i believe are the prayers of my parents and blessings of Allah SWT. Without help of Allah it was never possible.

I hope it helps.