As far as swap meets go, it's a pretty good one. You just never know what will show up. I would go on Saturday, just seemed to me to be more people willing/ready to deal than on Friday.
For your kids showing, are you talking about the county fair or the state fair? It would help if you know what classes are available to show in. Some shows have a split in each class for under a year and over a year old birds. Others only allow under a year old birds. And others don't specifiy.
That can make a difference as to when you hatch/purchase.
So yeah, go, have fun, meet some fellow addicts. (yes chicken raising is a disease!) There's always room for one more.