How to get a job im Medical Claims and Billing?

I got my certificate in Medical Claims and Billing in October 2007 and can not get a job or and interview.I would love to work from home as a medical biller so i can take care of my young son. But every time i apply I”m told that I have no experience and their not willing to give me a chance. Can someone tell me how I can get a job in this field. I fill that I wasted my time and money. I need some suggestions.