Red Sox Nation
Costco’s or Sam’s should be a start. When you get bigger http://www.sysco.com
used by many restaurants throughout US. Your first and foremost need to do some due dilligence and check out the competition. Buy from them see their menu and pricing. What can you do better and supply a niche that is not out there. Maybe serve FF if your trailer has a fryer and make them fresh. Something like that. Maybe sell breakfast sandwiches like a bagel, egg, ham and cheese very simple to make and only takes 90 seconds to cook.