Light slad dressings

You can get used to skipping it or using fresh lemon juice or flavored balsamic vinegar.
Here is one from Joel Fuhrman that you can modify:
http://www.blenderbabes.com/lifestyle-diet/egg-free/dr-fuhrman-balsamic-vinaigrette/

Ingredients

1/2 cup filtered water
1/4 cup roasted garlic rice vinegar
2 tablespoons extra virgin olive oil
1/4 cup balsamic vinegar
1/4 cup raisins (or grape fruit spread)
4 garlic cloves, pressed
1 teaspoon dried oregano
1/2 teaspoon dried basil
1/2 teaspoon onion powder

Instructions
Add ingredients to jar in order listed and secure lid.
For Blendtec: Press the BATTERS/DRESSINGS button
For Vitamix: Start on variable speed # 1, turn the machine on and slowly increase to speed 10, then flip to High. Blend for 25-35 seconds or until desired consistency is reached.

Classic vinaigrette is 3 parts oil to 1 part vinegar or lemon. A couple of dressings which are lower in fat than classic vinaigrette are:

1. Classic buttermilk ranch. Main ingredient is buttermilk which is low fat, being the by product of making butter. Use the smaller quantity of mayo and sour cream in this recipe. http://www.huffingtonpost.com/2013/08/19/ranch-dressing-recipe_n_3769342.html

2. Asian-influenced. 1 part sesame oil, 1 part balsamic vinegar, 1 part soy sauce.

3. Some south east asian dressings are oil free such as Nuoc Cham from Vietnam or the dressing used for Thai Som Tam. These dressings do contain sugar though. http://www.epicurious.com/recipes/food/views/Nuoc-Cham-10604

4. If you like a creamy texture, some Japanese dressings are thickened with pureed tofu and sesame paste. http://blog.umamimart.com/2011/02/japanify-shira-ae-sesame-tofu-dressing/

Kraft has a lot of calorie wise dressings without artificial sweeteners in them. In fact, I don't think I've ever had one of theirs that had artificial sweeteners in it. I like their legu-fruit & veg berry balsamic at the moment. It's 30 cal/tbsp, but a bit high in sugar (4g/tbsp).