I know most of these:
Japanese: 料理人(りょうりにん, ryōrinin) -- this is a person who prepares food, i.e. a cook. 調理師 (ちょうりし, chōrishi) -- This is a head chef or master of cooking. シェフ(shefu) -- This looks like an English loanword of "SHEFU." I don't have any examples of usage, but I suspect it refers to a (cooking) chef. コック(kokku) -- Cook, from the Dutch word for cook.
I'd update the page, but the markup is cursedly confusing. If someone who understands it wanders by, feel free to update the Japanese portion as above. - Ahelps 21:21, 3 January 2008 (UTC)