The names of some of the good reference Books for preparation of TNPSC or Tamil Nadu Public Service Commission Group 1 Exam are as follows:

1. State Board books are considered as primary source of TNPSC Exam question setting for all Group Examination. So you should study following school text books.
i) Social Science Books - 6th to 10th Std
ii)Science Books - 6th to 10th Std, (Additional 11th,12th Botany and Zoology if you have time)
iii)Polity - 11th,12th Political Science
iv)Economy - 11th,12th Economics Books
v)Geography -11th,12th Geography Books
vi)Indian Culture - 12th Indian Culture Book

2.History
i)Prof.J.Dharmarajan's Tamilnadu History
ii)K.Venkadesan. India Freedom Struggle

3.Indian Polity
i)Lakshi Kanth - Indian Polity

4.Indian Economy
i)Pratiyogita Darban's Indian Economy & Ramesh Singh's Indian Economy Book

5.Geography
i)Oxford School Atlas
ii)Spectrum Publication -Indian Geography
6.Tamilndu Language and Culture (Mains Exam)
i)தமிழ் இலக்கிய தகவல் களஞ்கியம் - தேவிரா
ii) தமிழ் இலக்கிய வரலாறு - மு . வரதராஜன்

7.Current Affairs
i)The Hindu, Dinamani,
ii)Competitive Success Review/Civil Service Chronicle/Competition Wizard/Shankar IAS Acadamy's Civilpedia(any one of these magazine)
iii)Yojana/Thittam

8.Science & Technology
i)Science & Tech by Spectrum Publications

9.India Year Book by Government of India

10.Aptitude (50 marks in Group 1 Exam)
i)A Modern Approach to Verbal Reasoning by R.S. Agarwal
ii)Quantitative Aptitude by R.S.Agarwal
iii)Objective Arithmetic - R. S. Agarwal

11.Guide Books for General Studies (Not Important, if you study all the above mentioned books). Any one of the Guides like Tata Mc Graw Hill, Spectrum or Pearson.