See if they have a facebook page and if so, unleash with a massive rant on it.
A few years ago, I had to cancel 5 return tickets to Europe through flight center. They said it would take around 12 weeks for the refund (around 12k) as they had to chase Qantas and other carriers for the money first.
So I had a whinge on their facebook page and within a few hours I was contacted by someone from flight center and had a full refund by the end of the week.
