These books only contain puzzles with a group size of 9 on a 21x21 grid. These puzzles consist of five overlapped 9x9 Sudoku-type puzzles 'quilted' together to form a larger 21x21 puzzle and are often found in many Sunday newspapers under a variety of names. The 'Variations on Sudoku-by5' books contain a few examples of the different puzzle types available in this catalogue, with puzzles at all of the available difficulty levels. The 'Variations' books are available either by level, i.e., all the puzzles in the book are the same level of difficulty (easy, difficult, challenging, etc) or with all levels in a single (but much larger) book. For editions that are available in print, the on-line information includes detailed step-by-step solutions for each puzzle, as well as other information available in all eBook editions.
| Book Title | Vol | Puzzle Count | On-Line Info | Edition Availability | |||
| Paperback | |||||||
| Variations on Sudoku-by5 | 1 | 105 | Solutions | $7.99 | eStore | ||
| Variations on Easy Sudoku-by5 | 1 | 40 | Solutions | Free | |||
| Variations on Medium Sudoku-by5 | 1 | 40 | Solutions | Free | |||
| Variations on Difficult Sudoku-by5 | 1 | 40 | Solutions | Free | |||
| Variations on Challenging Sudoku-by5 | 1 | 40 | Solutions | Free | |||
| Variations on Tournament Sudoku-by5 | 1 | 40 | Solutions | Free | |||
| Variations on TournamentPlus Sudoku-by5 | 1 | 40 | Solutions | Free | |||
| Variations on Perplexing Sudoku-by5 | 1 | 40 | Solutions | Free | |||
| Easy Sudoku-by5 | 1 | 100 | Solutions | $7.99 | eStore | ||
| Medium Sudoku-by5 | 1 | 100 | Solutions | $7.99 | eStore | ||
| Difficult Sudoku-by5 | 1 | 100 | Solutions | $7.99 | eStore | ||
| Challenging Sudoku-by5 | 1 | 100 | Solutions | $7.99 | eStore | ||
| Tournament Sudoku-by5 | 1 | 100 | Solutions | $7.99 | eStore | ||
| TournamentPlus Sudoku-by5 | 1 | 100 | Solutions | $7.99 | eStore | ||
| Perplexing Sudoku-by5 | 1 | 100 | Solutions | $7.99 | eStore | ||