Well the problem is you do not really know how good an internet radio is, especially with free services. I mean you could literally play your best set with ZERO people listening, as many show you also “dead” connections.
The only really reliable internet radios are the more commercial ones or the ones listed on big listing projects such as iTunes radio listing, Tunemark etc.
Then there are some internet radios that are tied to some other service (in many occasions online games) one of the most prominent is eve-radio.com which is tied to EVE Online.
Those usually do not bulls*t you about how many listeners you have.
I would NEVER pay to play. You should always get paid to play not the other way around. In many cases it is not much, but hey.
About software: You can usually broadcast very easy if the radio is at least half-professional. With the VDJ Pro Version you can broadcast directly from VDJ, that is why many broadcast DJs use VDJ. Then there is SAM broadcaster, but this is more geared towards a talking moderating DJ and quite expensive.
Then there are solutions like icecast, tune cast,… and many more that capture audio sources of your computer and direct them into a broadcast stream. This setup is a bit more difficult, but usually the guys from the radio help you setup via TeamViewer or a similar software.
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