Has anyone had success running a radio ad campaign?

[JoeClark]

Hello,

I am researching the benefits of running a large radio campaign and I am wondering if anyone here has prior radio advertising experience? My goal is not at all branding, but rather direct sales. I would be directing the radio listeners to my website.
So I am wondering how the ROI of radio ads compares to web ads?

Does anyone have knowledge of how to purchase and setup a large radio campaign? I went through many resources and checked Advertising Campaign Examples but,I haven't found a clear source for rates and to purchase ads. Any advice?

Any help will be appreciated.
Thank you.