Here are some that I have come across while looking for one. Feel free to add to the list. http://www.elegantthemes.com/demo/?theme=eList http://www.inkthemes.com/wp-themes/geocraft-directory-listing-wordpress-theme http://directorypress.net/directory-template http://sitemile.com/products/buzzler-business-directory-theme http://www.premiumpress.com/directoryscript http://www.geotheme.com
I am not sure whether the above mentioned wordpress Directory Themes are worth. Let other members comeup with their experience with wordpress Directory Themes