Top preparatory books recommended for UPSC Civil Services Examination include the "Indian Polity" by M. Laxmikanth, "Modern History of India" by Bipan Chandra, and "Economic Survey" for economic insights. Candidates should also refer to "India Year Book" for comprehensive current affairs. "General Studies" books by various authors like D. R. Khullar offer in-depth understanding of essential subjects. Additionally, aspirants often use "Lexicon for Ethics" for the Ethics paper. Using a blend of these resources contributes to a well-rounded preparation strategy aligned with the UPSC syllabus.