I started making everything in our house onion free. We had to do this after realizing my husband's sensitivity to onions. Salad dressing is easier to make than I thought. I guess I came from the generation that that everything came out of a package or box. I'm glad I'm not passing that down to my girls. :)
If you check out All Recipes you will see there are plenty of things you can add to an Italian Dressing. The basics are this:
3parts oil to 1 part vinegar, a little less water than vinegar and spices.
For ours we use apple cider vinegar, olive oil, and the spices you can see above with a little crushed red pepper that isn't labeled.