The Stairway To Given complements The Giving Path by adding to our understanding of the process listeners go through before they become contributors.
Listener-Focused Fundraising - Though best known for finding that listeners disliked the sound of ringing phones during fund drives, Listener-Focused Fundraising demonstrated the importance of good off-air fundraising and new ways to bring programming values to pledge drives.
Fundamentals In Brief is an excellent summary of the public radio audience basics. It's from Audience 98, a comprehensive study of public radio listeners, their listening habits, and their perceptions about public radio.
Turning Listeners Into Givers is a report from George Bailey at Walrus Research. It demonstrates the role programming and service to the listener plays in creating prospective donors to public radio.
Heavy Givers is the follow-up report to Turning Listeners Into Givers. It examines why some people give more money to public radio than others.