I bought an electronic gizmo called the Bark Solver and put it in the front hallway where Bailey always runs to and barks. I bought it at Pet Edge for around $30.00. You can set the frequncey to to high (dog only) pitch or to audible. She does not like it at all and will stop in mid bark.
At night (when she doesn't sleep with our daughter) and it is pine cone falling season
She can superman fly off the bed to run to the door to protect us.
All night long...sighhhh.. the bark solver and a toy squirt gun worked wonders.
I have one that barks and one that doesn't. Have you tried dog training classes? Worked well for my friends Boxer who would bark at every little noise.
Good Luck