K.D.
I haven't tried this specifically on vomit but it has worked on everything else I have used. Good old everyday shaving cream (make sure it is the white stuff!) Wring out a wet washcloth over the spot you want to clean (make sure it gets the whole spot really wet. Spray on the shaving cream again make sure it is covered. Let it sit for about 5 minutes. Then, with the same damp washcloth dab at the stain. Good luck!