Edinburgh Croquet Club [more]
Brief outline of the game.
http://www.ccir.ed.ac.uk/~fmi/croquet.html

Jersey Croquet Club [more]
History, attractions, and descriptions of the game.
http://www.mnlg.com/jcc/frames/theGame.html

Masters Games [more]
rules of the game.
http://www.mastersgames.com/rules/croquet-rules.htm

Oakley Woods Croquet Equipment [more]
What is croquet? A bit of history, short glossary, International Six-Wicket Croquet, American Six-Wicket Croquet, Golf Croquet, American Nine-Wicket Croquet.
http://www.oakleywoods.com/whatis/aboutcroquet.htm

United States Croquet Association (USCA) [more]
Overview of croquet in America, from backyard game to worldclass sport.
http://www.croquetamerica.com/croquet/introduction/