As per your demand here I am suggesting you Best Books for preparation of TNPSC Group 2 Exam

PART ‐ A (Objective Type

Unit-I Role and impact of science and Technology in the Development of India and Tamil Nadu.
Tata McGraw Hill's Science & Technology for Civil Services Examinations by Ashok Kumar Singh

Unit-II Administration of Union and States with special reference to Tamil Nadu
Indian Polity By M Laxmikanth
6-10th Std Civics Portion of State Board Books
11th,12th Polity – State Board Books

Unit-III Socio - Economic Issues in India/ Tamil Nadu
Social Problems in India by RAM AHUJA

UPSC Civil Services Main Exam - Issues Relating to Social Development by B. Ramaswamy


Part -B (Descriptive Type )

(a). Current issues at National Level
Editorials, Essays and Current Events from The Hindu (English, Tamil) , Dinamani News Papers
Thittam , Any Monthly Current Affairs Magazine for last one year (find it from a public library)

(b) Current issues at
State Level
Editorials, Essays and Current Events from The Hindu (English, Tamil) , Dinamani News Papers.
Yojana/Thittam, Frontline Magazine, Any Monthly Current Affairs Magazine for last one year