How to represent local non-profits at shows?

Hi all,

I joined this site because I thought the intention of the group was to be able to showcase local organizations at Brett Dennen's concerts. However, I can't find any information on the site as to how to go about doing this. I am seeing Brett this Friday at a venue in Northern Virginia, an area in which I am part of a local environmental sustainability organization. I would like to be part of the scene after the show where fans can take some of the the energy from their show and direct it to help local groups. Can somebody please tell me how this is organized/setup? Do I just show up at the venue with a stack of fliers?!!