Send audio from my laptop to my iPhone over Bluetooth
According to your comment, you would be happy with a Ubuntu solution where WiFi works. Therefore, follow this thread at askubuntu.com. 

What they basically suggest, is:


  
  Create a webserver with IceCast under Ubuntu und stream your audio from there (Here is a Howto)
  Connect your iPhone via an IceCast compatible app.
  Now you can connect your iPhone to your IceCast server and stream audio
  


If this doesn't work for you because of complexity, follow the lead of:


  
  creating your own local streaming server on Ubuntu, or just create a "normal server" 
  and then access the files from there on your iPhone with a app which
  can connect to that server.
  




A Bluetooth solution for a Windows environment is over here.