Useful links – The World Puzzle Federation

logicmastersindia.com – Indian online sudoku and logical tournament every month. Authors from all over the world
www.argio-logic.net – Italian online tournament every week, Roulette, Contest, Classic only Contest, Hybrids and Headshrinker
www.puzzlefountain.com – almost every week online tournaments with logical puzzles, occasionally also sudoku tournaments
www.e-sudoku.fr – French web site with online classic sudoku
croco-puzzle.com – German online logical puzzles every day
killersudokuonline.com – online source of killer sudoku puzzles
kwontomloop.com – every day source of Slither link puzzles
www.sachsentext.de – variety of online sudoku and logical puzzles
www.speedsudoku.com – speed sudoku for 2-8 players
cs.sudokucup.com – Czech online sudoku tournament – twice a year
forsmarts.com – logic games and puzzles by V. Portugalov
www.puzzleup.com – Turkish online logical puzzles tournament
www.fed-sudoku.eu – every day online sudoku