Lack of a car and issues?

I lost my car, it was reposed because my last job cut my hours. Yeah I made a mistake and I am really paying for it. How do you get a car with bad credit and no down payment? Is there a Charity that can help? I do have children, does that help? Without a car, I will lose my job. Did I mention that I don't have a co-signer? Anyone? No I can't rip off a car :-)