Read my response here, which applies to both vinegar and oil. You'll see "whys" in the link I provided that explain why neither are meant for human consumption:
Awsome! Thank you! :)
I have a "magic bullet", which is basically a small blender. I use that to make my dressings. Search salad dressing on this site and you will find tons of recipes.
Yes, I think an avocado with lemon juice could easily replace oil and vinegar.
I second that! What I use most often for a quick dressing--and it just takes some mashing up! I was an oil/vinegar girl myself.