OP this post is very frustrating. The plan to 'get as far away as possible' is the most dangerous thing you can do because you're just taking your vulnerable children and running away to who knows where.
I'm very surprised that none of the domestic abuse organisations or refuges you've been emailing over the past few days have got back to you. It's very remiss of all of them and very surprising.
The reason you've been advised to contact a domestic abuse organisation is because they will help you to a. find somewhere to go and b. help you plan it.
You and a load of children booking into a hotel or whatever is pretty identifiable if he has people out looking for you. Then where are you going to go?
My advice to you is to tell him you're going shopping tomorrow and make some calls. If you have a car, (you haven't mentioned if you have or not) you can call from the car. Call the National Domestic Abuse helpline and they can search for a refuge for you. They can help you to make a safety plan and they can advise on the best way to leave.
If you cannot get in contact with the helpline (they can be difficult to get in contact with) then call any of the domestic abuse organisations you have contacted from the link. I'm posting it again here. They will do the searching for you and if they can't find anything, they will advise you on how best to leave safely.
Your other option is what you did before. Tell him you have an appointment somewhere and, if he waits outside, that's great. Ask whoever you're with to help you or use the opportunity you're away from him to make some calls.
Here's the helpline: 0808 2000 247
Other ways of getting help: contact social services, GP, hospital, police, school - all of those organisations have links to services who can help.