Well as far as I know the world series of poker is an annual event. What you should probably do with that domain is feature poker rooms that allow players to win a seat to this poker tournament. All prima powered poker rooms do this.
The unfortunate thing about promoting prima poker rooms is that they earn little in comparison to Party Poker, but if you land a few good players they can pay off. And while they may earn little in comparison to party poker, from my experience they earn the second most.
I have a page devoted to this tournament on my website you might want to take a look for an idea:
http://www.pokertournaments.org/worldpoker.html
Antoine