I've been making my own salad dressings and other various dressings for the last few months while trying to track down an allergen free dressing. Not that I don't like making dressings, but sometimes it's just awesome to be able to grab something from a bottle and drizzle it over everything with no prep work required. Maple Grove Farms makes two different Raspberry Vinagrettes which are Allergen free and Gluten free (free of the top 8 allergens). They come in sugar free and fat free variations. I use the sugar free version, and it tastes fabulous.
Have you found any great allergen free dressings?