The Beech 1900D landed on runway 24, and was cleared to taxi to the ramp. As the airplane entered the ramp area, the flight crew planned to stop beyond the hold-short line, to wait for another airplane to exit gate 25. As the flight crew crossed the hold-short line, and were almost at a complete stop, they felt a “buffet,” which became a “large jolt,” on the left side of the fuselage. After realizing a fuel truck impacted the left engine and propeller, the captain shut down the engines, and evacuated the passengers from the right window emergency exit. PROBABLE CAUSE: “The fuel truck driver’s failure to maintain clearance with a taxiing airplane, resulting in the collision between the fuel truck and the airplane. A factor in the accident was the night condition.”