The company has signed a six-figure deal to back the event, which will be held in December 2003 at a venue in Essex. Ladbrokes will have the option to extend the tie-up for a further three years.
The tournament will also include one place reserved for an amateur darts player as part of a separate tie-up with The People newspaper.
Thousands of hopefuls will take part in pub challenges to register the highest score with nine darts. The 16 players with the highest scores will then be brought together for the SP 9-Dart Challenge where they will fight it out against each other for the 40th place in next year's World Championship.
It is believed to be the first major sporting event at which a place is reserved for the winner of a marketing campaign.
The tournament will be broadcast live on Sky Sports, with every contestant guaranteed a minimum £2500 in prize money.