Configure an Airport to connect to internet via a wireless hotspot?
Here's how I would do it:

I would use any old router to bridge from the hotspot into your house, making sure that the bridge is in optimal distance of the Provider Hotspot. 

Once I have that configured and I know I have connectivity to the internet, I would hardwire the Airport Extreme into the bridge to have the home networking functionality, as set up through Airport Utility.