We flew with Lifeline Pilots which is a non-profit organization that assists with air travel. They do not require a financial status level to qualify. You just fill out some paperwork and have a doctor sign off saying that your child is medically stable enough to fly.
We stayed at the Ronald McDonald House. It costs $15/night but if you are unable to pay then they will still accomodate you. You fill out your reservation online and then check with them the morning of your trip to make sure that you have a room. This was a wonderful way to meet other clubfoot kids (it's clubfoot land in Iowa so many of the residents at the Ronald McDonald house were clubfoot children.). If the RMDH can not accomodate you then they will set you up at a local hotel with a discounted rate. The RMDH also supplies food for you while you stay.
Other websites to assist with travel expenses include:
-Air Care Alliance
-Childrens Flight of Hope
-Corporate Angel Network
-Mercy Medical Airlift
-Miracle Flights for Kids
-Northwest Airlines, Kid Cares Program
-American Airlines, Advantage Miles for Kids in Need