I would not assume anyone is paying to get on "the list". As an event planner, their first goal is making their clients event perfect, not a quick buck. Go in and prove you have a good product, are reliable, are licensed, etc. You have to show them you are legit and that they can trust you to make the event planner look like a rock star at the end of the event. The people on the list make the planner look good, that's all.
If you have an advertising budget, why don't you throw a private party somewhere and invite event planners in the area and don't forget to hit the local hotel planners as well. Have your private event, wow them with your food, your presentation and give a quick rundown of your capabilities. Then follow up with everyone asking to take care of a small party for them.
Little Miss BBQ