If you are going to the one in Cincinnati, OH then there show contact info is listed here,you can email the chairs and them.
http://www.daylilies.org/Exhib...
You can also go to the club website for info and other contact info
http://www.gcdhs.org/index.htm...
They have a list of hostas for sale for the Hosta Show (which was yesterday) so maybe once they get settled from that they will update the website and have the list of daylilies for sale as well.