An USAF T-38 aircraft and a Cessna 206 aircraft collided in mid-air during visual flight operations in a Military Operations Area. Radar data revealed that the overtaking T-38 collided with the Cessna 206 from the right. The Cessna was on a local government contract terrain photo mission and had almost completed a left 360 degree turn. The T-38 was transiting the MOA in connection with a military mission. Both aircraft were operating under VFR and were not in contact with the MOA controllers. Neither pilot was required to establish or maintain positive radio or radar contact with the air traffic control facility responsible for the area. However, the Airman's Information Manual states 'Pilots operating under VFR should exercise extreme caution while flying within a MOA... Prior to entering an active MOA, pilots should contact the controlling agency for traffic advisories.' Radar and radio assistance was available to either pilot. The T-38 was using a transponder with Mode C readout. The collision occurred at about 8,700 feet MSL.