Here are a few ideas. Seems that the "barn party wedding theme" is alive and well. If I were much younger and of the marrying age, it would be appropriate, but I think I'd prefer something more formal. Anyway, take a look and maybe this will inspire a few others to put the party planning mode in full gear.
(From Bubby & Bean)
(From New England Fine Living.com)
(From Country Living)
Enjoy the lovely fall day!