Where to sell offline advertising nationally?

Hi Warriors,

I'm in a unique situation to be able to offer ads on my mobile business that I just purchased but I'm looking for a way to market that nationally instead of just locally. I have a specialty drink and mobie dj trailer that I am readying for the '09 season and I am going to offer ads on the customer side counter ala placemat type advertising like you see in restaurants. These will be in 1" blocks and Im settled in at $199 a block as my surveying has shown that is a good price point. Im also looking at doing a prelaunch special as well. ive gotten a tremendous response locally and have already sold a bunch but wanted to be able to sell out the lot quicker so that I can continue to focus o n my other marketing efforts.

What would be a good marketing method to go about this? I don't know about the ebay option but I have thought of it. I've also thought about a possible joiint venture. The ads can be bigger than 1" if they want to purchase 2 or more, and I'm sure the prelaunch special I do will help that as well. My target audience will generally be a younger to a more sophisticated person as that's what my target drinks run. Besides festivals and local events I will also be doing some private events as well.

Well that's it in a nutshell.

Thanks for any replies,

-Bob