Allow a user only to submit once his content

Hi . . .
is there a way-hack to control how many times a user can submit his content on a specific content type-taxonomy related ?
e.g i want to create a contest content type where a user can only submit only 1 post at each contest . Every now and then i plan to have a new contest so what i basically want is to to check the database if the current logged user has at least 1 post at each contest the create contest->submit to contest link will be deactivated.