Hello SC, did you ever make it to CelticFest and/or the recent Louisiana festivals? Make copious notes about what pleased and/or annoyed you if you did, it might help you avoid some problems. And for heaven's sake, go to the Highland Games in Jackson, LA in November, they'll have music stages and you'll learn a lot and can make a few contacts.

Highland Games

Is this in Natchez, Woodville, Liberty, Port Gibson?

Regarding performers, how much do you have to tie down to the exact time period of the founding? So many groups which play at re-enactments are Civil War time period. If that's close enough and you can use some of them, do look into booking "Unreconstructed" out of Alabama, they would add a lot of atmosphere and knowledge. They don't do a lot of 'civil war songs' at all, just a nice variety of instrumental and vocals from way back when and where. Whatever you do, don't dawdle on bookings, a lot of these groups have festival bookings lined up for at least a year in advance, and nice spring weekends get locked up in a hurry by other festivals.

Jim Flanagan is a short drive away in Hattiesburg, do get in touch with him, he has a big Irish & British Isles repertoire which includes a lot of genuinely old stuff, and could probably put together a good set of material which would be suitable for your period, but again book ahead.

If you want to get farther back in history and you start right now, you might be able to get a colonial balladeer or two to come down from Williamsburg Virginia, at least everything they sing would predate your timeframe and therefore be stuff that could have been sung around that time. If you have some humanities grant money involved in this bicentennial, have the grantwriter get in touch with the Colonial Williamsburg people and maybe together they could find some travel funds to make it happen.