Contracting/consulting covers a multitude of sins, so I think your first step is to think about the areas you could plausibly contract/consult in. When you've got that worked out, it will be a lot easier to see what qualifications/courses (if any) might help.
For example, an MBA is a good general purpose business qualification, but if you are middle aged and have never had any corporate experience, it's unlikely it'll help you get a job on its own.
There are a very few employers who will take people into contracting/consulting with little prior experience, but they are mostly graduate opportunities for young people. Going into these fields in later life is all about selling the experience and expertise that you already have.
HTH.