My Vet is both large and small animal which is good and bad for us since we do have BOTH large and small animals and I do use him for both.
I also am personal friends w/the asst. office manager so I have never had problems being fit in and in the past before she worked there if it was an emergency I would tell the receptionist I would be the last appointment of the day and they could charge me an ER charge if they wanted to.
My Vet will also make housecalls for certain things.....definitely if it is an appt. to put an animal to sleep. I do have my Vet's cell number though I would not use it unless I REALLY, REALLY needed to because I think I got it when he called me from his cell and I kept it. I do have another large animal Vet that I used last year when my mare was sick and that Vet did give me his cell number.