I wouldn't encourage getting an MBA unless you are currently working in your desired field and have had superiors encourage you to get one to further your career.
I worked while I put myself through school. When I started I had a basic office job making $25k and went to school at night. I had no money so i took a job as a personal trainer so I could make more and set my own hours. I continued to do so while earning my MBA and by the time I was done I was making more as a trainer than any of my job offers. Plus EVERY interviewer would ask why I left my office job to become a personal trainer (implying that my education didn't mean anything without the job experience).
Basically if they are looking for someone with an MBA, they are also looking for someone with 5-10 years experience in that field. You (and your resume) should heavily focus on all of the skills and attributes you have acquired by working for yourself and how those experiences increase the value of what you can contribute to a company.