Yah, go APA or BCA. APA if you want to be more hands-off - let the local league operator handle things - or BCA if you want to run it yourself (or have a staffer run it).
Once you figure out the route you're going to take, print up fliers about it and tack'em up around your room. Do this a few weeks in advance - give folks plenty of time to put together teams before the league starts.
You might even put up some team sign-up sheets, so folks can put their names/phone numbers down, either grouped by teams-to-be-formed or one big pile so folks can contact each other and make plans for teams.
Also, leagues take some time to get rolling. Don't expect a full house the first session. It may take a year before you're getting the weekly traffic you want. Be patient!