Core subjects

• Polity: Laxmikanth (selective chapters)
• History/Geography/Economy: NCERTs (Class 6–12)
• Jharkhand GK: A dedicated Jharkhand Samanya Gyan book (latest edition)
• Current Affairs: Monthly magazine + state news

Free resources

• Official portals (jpsc.gov.in, jssc.jharkhand.gov.in) for syllabus and PYQs
• Previous-year question papers — solve at least 5 years
• This site's Syllabus, Mock Test and Current Affairs sections

Advice

Limit your resources. Revision of a few good books beats hoarding many.