Jason interviewed on Wisconsin Public Radio's “To the Best of our Knowledge” - information about it as well as access to audio of the program is available here.

Once you've accessed the audio scroll to 29:34 for the start of the interview.

Here's a brief description of it from WPR (under "Segment 3"):

"Jason Reitman wrote and directed the film "Thank You for Smoking." He tells Anne Strainchamps the film is based on Christopher Buckley's book, and features Sam Elliot as the Marlborough Man. And we hear some very funny and totally subversive clips. Also, Boz Temple-Morris was co-founder and Marketing Director of the Enlightened Tobacco Company, makers of Death Cigarettes. He tells Steve Paulson the company was all about truth in advertising."