Interviewer said they'd cover my travel costs, but haven't heard from them since?

I live in LA and had a phone interview with a company interstate in Chicago about 5 weeks ago now. They said they were very impressed and that I'd hear from them "in a few days" to set-up a face-to-face interview. They rang me almost two weeks later and said they'd like to meet face-to-face and that they'd arrange to pick me up from the airport to take me to their office. I asked if they would cover the cost of my airfares and they said they would.

We met face to face a few days later, I was shown around the office and more about what the job would entail. Went through a few other things and left with them saying I would hear from them in two-three days regarding salary negotiation and a possible job offer (but they just had to discuss a few more things internally). The vibe I got from the office, company, director and employees and their overall professionalism or lack thereof made me decide I wouldn't want to work there, but that it besides the point.

It's now been two weeks and I haven't heard anything. I sent them a follow-up e-mail on Thursday asking when I would be reimbursed for my travel costs, as since I'm a recent graduate I don't exactly have a whole lot of money and this means quite a bit.

What else can I do? Just wait? I kind of need this money back.