Directions are available at this link.
Please be aware that while the address number is 6595, you will want to point your GPS unit (if navigating that way) to 6559 instead or you will overshoot your destination.
If approaching from the south, the following directions may suit you better:
Take I-65 North to exit 76 (Edinburgh/US 31). Go north on US 31 to Hospital Road (this is also how to get to the old Simple Day site and Camp Atterbury). Turn left (west). Follow Hospital Road west through Nineveh to County Road 125 West. Turn right (north) and the site will be about a mile north on the right. Look for the stone columns with the FFA logo on them.