- sudoku.com How To
Excellent description of solving methods. Doesn't cover the most advanced techniques.
- Solving Sudoku
Simple and advanced techniques, nicely illustrated.
- Astraware Sudoku
Simple and advanced techniques, nicely illustrated.
- Conceptis Puzzles
Both simple and advanced techniques, nicely illustrated.
- SadMan
Simple and advanced techniques described.
- Solve Sudoku
Step-by-step illustrated guides to solving example puzzles.
- Nikoli (Flash)
Illustrated guide to the basics of sudoku for beginners.
