You can start with a book you know or are given in your syllabus or reading list:
The Puzzle Instinct - The Meaning of Puzzles in Human Life. Marcel Danesi.
Look at the LCSH to explore the topic:
Why Puzzles?
Puzzle-Making through the Ages
Puzzle-Solving as Insight Thinking
The Puzzle Instinct
Puzzling Language: Riddles, Anagrams, and Other Verbal Perplexities
Riddles
Anagrams
Cryptograms
Rebuses
Crosswords
The Janus-Faced Nature of Language
Puzzling Pictures: Optical Illusions, Mazes, and Other Visual Mind-Bogglers
Visual Trickery
Geometrical Mind-Bogglers
Puzzles in Geometrical Dissection and Arrangement
Mazes
Order and Chaos
Puzzling Logic: Deductions, Paradoxes, and Other Forms of Mind Play
Deduction Puzzles
Truth Puzzles
Deception Puzzles