Many of the professionals started when they were very little and had their own little music recorder and pretended to be a radio station. But the majority grew into this during their school time.
On school you had to choice choires, or you had to join certain clubs. One of these clubs of course was the radio club. The cool thing about it was, you could test your skills, you could test what ever you wanted to do on it as the property was on school and the listeners were no paying clients yet.
Also I believe in many states it is not approved yet to advertise on the local school radio stations although it is a nice way to reach client if they are listening to it.
Tip of the day, try listening to the Tulsa collega based: RSU, 91.3 FM.