Sorry, no actual advice concerning the legal way of doing it, but I did hear about a pirate station in the neighborhood from a fellow just last night. That's something I've never considered, but it appears there must be illegal methods out there to get involved with if you're of a mind.
There is also PalTalk. Various folks at this site have hosted online open mics there, and I've been a participant in those events, but there is also a new feature that I've noticed where one can host a radio show as well. I have not explored that particular aspect of it myself, but I understand that anyone can use the site to host their own online radio show, and yes there are advertizements that show up if you use the free edition but they're easily ignored. The cost of the basic service is free but there are additional features like streaming video that can be added for a fee, (the capability to show streaming video of yourself and also view those who may have the same feature, who are visiting your room via your monitor). I understand that the paid service also eliminates any ads that appear on the free version. Sorry, I've never explored this part so I'm not aware of what it costs.
All you need to do then is email folks to let them know when and where you are on air so that they can listen in.
Most of the regular rooms are a sort of invitational disc spinning party. You enter the room and can take turns giving your favorite disc a spin while others in the room listen in. There are also kareoke, open mic, just listening or simply chat rooms. In addition to what can be heard, via those who participate, there's a "real-time" text chat that happens among those in the room who are listening in or waiting their turn to contribute.
I don't know if you've explored PalTalk.com, but it may be a good way to start this show of yours. It can, if nothing else, give you a platform with which to begin and launch your format. Then simply save the shows by archiving them on a disc or by saving them to tape and when you find other online outlets for them you can re-release them. The real-time text chat forum feature makes it possible to receive immediate feeback from your target audience and is an excellent means of gaining insight from your listeners about your show.
Click this link to PalTalk and you can explore it further.
I hope this helps and wish you the best of luck in your efforts.
We'll be listening for ya, Reg