Here is a website that might interest anyone who hasn't found it, yet:
The guy who does it produced and recorded many live Punk, New Wave, and other bands for various radio shows in San Francisco Bay Area in the late 1970s and 1980s. Some of the listings have 30 second samples. He apparently will sell CD-Rs or mp3s of any of the shows. It's an amazing list! Has anyone bought any of his shows?