If you're looking to find western wedding dresses that are more than just fringe and lace, you can adapt many designer dresses to look right at home for your country themed nuptials.
This dress is called "Magnolia" by Mariona. The shorter length with the upswept front can still showcase your white bridal boots and leave you plenty of comfort room to swing around your barn dance without getting all tangled up in a long skirt.
Give it more western flavor by addition a white Stetson (with an attached veil) and maybe a lace shawl or bolero jacket for warmth against the cool night air.