From the "unofficial" website:
AMF 18 (2014) will be held Monday August 4th till Thursday August 14th 2014.
the location will be emailed or texted to you when the location is finalized. This is usually the first day of the festival, not likely to know where it is before that, because no one does (literally no one, the scouts find a rough idea of where, and the first people to show up to that area kind of define the center of the site, then inform everyone else).
Sign up here to help with organization, and be sure to get the info of the location when it is available.