Have you taught your dogs the "no bark" command? That's a good place to start.
Are your dogs barking at the door when their is a noise, disturbance, etc.? My Jack Russell has this problem. What I did was follow something I saw on the Dog Whisperer and in a book by Brian Kilcommons. I claim the space. First, this involves using my shaker can (a soda can with a few coins in it) to get the dogs' attention. When Misha would bark, I'd shake the can and give the "no bark" command.
The shaker can was effective sometimes. But, I didn't want to shake the can every time she barked. So, I started claiming the front door. This is how I do it. When she runs to the front door to bark, I put myself between her and the door. I don't let her get to it. I point away from the door (I try to be as authoritative as possible with my posture and body language), and I give the commands "no bark" and "go".
It takes awhile for them to catch on. With Misha, I've added a command "Thank you...you told me". I know. It probably sounds silly. But, when she hears me say this, a lot of times backs off. She has figured out that I will check the door or window and she walks away.
My methods aren't perfect. We are still working on it. For instance, when a stranger is at the door, it is complicated because she jumps up and down like she is on a trampoline. The only thing that works when she is that riled is to put the leash on her and take her away from the door.
It's a little more complicated in your situation because you have three dogs. My brother has 3 dogs. He found that using one of those bark inhibiting collars (his gave a sound) on the dog that barked the most was helpful. By quieting that dog, the others followed suit.
The important thing with whatever method you try is to remain calm. They amp up a notch when you are excited.
