Can I ask you whereabouts in the world you are? (This affects the licensing as it various between countries)..
In the UK, the license you need (assuming you are the organiser – that is who is responsible, not the DJ) will depend on your broadcast method and how people access the stream. For example, if you have a stream which is completely private (IE encrypted and only some of your friends can get on it and you have to give them a password) then the license amount will be reduced as it is not a public event..
It is the station owner not the DJ who is responsible for the license though (Unless of course that is one and the same person).
I suspect that many of the stations will be paid for with some form of advertising – not many other options out there – but many will be run as a hobby and therefore probably don’t need to make any profit…
bob6397