That didn't take long. I found an excellent article here:
Excessive Barking: A Common Dog Behavior Problem
Here is an excerpt from it:
General principles for controlling undesirable barking
If we want to control barking, we need a dog who can obey us and relax. The dog needs to look to her owner for behavior clues. If we can call her, have her lie down (dogs do not bark as much when lying down) and stay, we are well on the way to solving a nuisance barking problem. In addition, there are some common principles we can use in modifying barking behavior.
First, in most cases shouting "No" is only going to make matters worse since the dog is thinking you are barking too (and is probably happy you joined in).
Be consistent. Pick a one-word command e.g., "Enough" for the behavior you want and always use that word in the same tone of voice. Everyone in the household must use the same command and act identically.
Be patient with your dog and yourself. Changing behavior takes a lot of time, and you need to take it slowly, one step at a time. If you become angry at your dog, the chance to correctly modify the behavior will be gone.
Reward the dog for good behavior. Positive reinforcement is much more powerful than punishment. Physical punishment will do nothing but make your dog fearful of you and break down the bond you wish to have with her. Food treats are fine to use as a reward at first. Often, picking a very special treat like small pieces of cooked chicken or hot dog will make the reward seem even better. As time goes on, you will not give a treat every time, sometimes just rewarding with a "Good Dog" and a pat on the dog's chest.
Do not hug your dog, talk soothingly, or otherwise play into your dog's barking. Your dog may then believe there really was something of which to be alarmed, afraid, or anxious. This reinforces her behavior and she will likely bark even more the next time.
Control the situation. As much as possible, set up situations to use as training. Practice in short, frequent sessions, generally 5-10 minutes each.
Do not be afraid to ask an expert. Animal trainers, behaviorists, and your veterinarian can give you valuable advice. Having them witness your dog's barking episodes may give them valuable clues on helping you solve the barking problem.
Just as an aside... This is from Drs. Foster and Smith whom we have done business with for years with our fish. You may want to check them out.