Yo Sudoku
Welcome to Yo Sudoku, a site which lists the best places on the internet to find sudoku related items, whether it's puzzles, trivia, strategies or merchandise:
Saidwhat Sudoku
A collection of over 100 sudoku puzzles for you to enjoy
Asymmetrical Sudokus
A site with unlimited, dynamically generated sudokus and a sudoku solver, all free and online.
Available in German, Russian and English. Play Sudoku online! 3 levels! You can register for free with the possibility to save your unsolved sudokus. Members get points for every solved sudoku. Best members and best countries are shown on the page.
This is the 'official' sudoku site
Another good sudoku site you might like to visit.
This site lets you play sudoku online and also has an eBook of puzzles.