Usually the music what is purchased is purchased only to you and not for public.
I suggest you to use freeware music. There are tons of sites with tons of good artiasts. I find free music better than some crapy comercial music.
Sites where you can get music:http://www.scene.org/http://www.scene.org.....oups/sublogichttp://noerror.scene.org/http://www.bedroombr...?page=allalbumshttp://www.obscure.ch/http://www.realaudio.ch/index1.htmlhttp://www.textone.org/http://www.thinner.cc/http://www.wmrecordi...om/releases.htmhttp://www.dmusic.com/
there are tons of other sites more but these alone here should give enough different styles. Some are weird also, but if you mix them, then you may get really good shows.
As for the old stuff (every week new albums):http://www.basichip.com/http://www.weirdomus...m/downloads.htmhttp://www.vinylorph...talentshow.html
Don't know how legal the last pages are, but should be.
Just ask the permission of artists or if not, who cares
I also suggest you to visit different m3u radio stations and stuff, maybe they give you old mixes and shows or even make you some.
Like my favorite radio is http://www.kohviradio.com/
with its estonian soft electronics mostly, but there are other radios... I suggest you also peep into shared folder: http://www.kohviradio.com/shared/
As for radios, it is kind of boring to have only music. If someone gives me vocals, I can do the mixing by myself. I have some mixes, but since i don't have proper host, you can only get them via soulseek or something. My username is inkspot. Its like 66,6MB or so (192kbps) but I can reduce the quality even a bit lower than usual radio standard (as it is for the game from crapy radio) and you can convert it.
There are even places where you can get old commercials, hehe, I have some also. But the best way to get a good commercial, is to record one by own. Now we need someone with good voice, the crappy mic can be filtered if needed (if it is not SO crapy).
And besides, I have some friends who make really proffessional music. One is in commercial and the other (the best music ever) is in the army right now. The person in the army can make whatever style you give him
You may also drop in some places where music makers gather. Like other gaming forums, music forums, IRC, soulseek rooms and DC++ hubs (best).
Or still, you can always make the anarchisic "f*ck RIAA" radio station, hehe