During the early stages of internet radio, there was basically only one place where listeners could tune in and that was on their PC. Later, some internet stations became available on devices such as Roku or Tivo. Listeners could tune to their favorite stations on their TV's.
Today there are so many apps that play internet radio stations that sometimes we don't know where to begin. These apps can be downloaded to any mobile device and go anywhere that there is internet service.
You could even listen using your mobile phone service. I would recommend having an unlimited data plan first. Cars today have internet access and contain apps like Tunein where drivers could tune to internet radio stations.
My car is a bit older so I purchased a small transmitter and use bluetooth from my phone which connects to the transmitter and I could then tune to thousands of internet radio stations or listen to any audio from my phone. Once the transmitter is connected to the phone via bluetooth, just find a quiet FM frequency and tune the transmitter to that frequency. It works great in most places. Again I emphasize getting an unlimited data cell phone plan.
On my way up to my college reunion a few weeks ago I tuned to the college radio station WPSC to hear my colleagues and friends do their shows. I also use it to monitor Edgewater Gold Radio all the time. It works great, just like satellite radio.
I anticipate that access will continue to improve over the coming years. Look for some great things to come with internet radio!