I've seen him on TV, the guy is brilliant and can make the most complex issue understandable.
He is not on the radio in my area, but you can catch him online.
Tuesday
11 A.M. on WMNF Florida 88.5 FM (Listen on the web)
2 P.M. on KPFA Berkeley, CA 94.1 FM (Listen on the web)
Wednesday
1 P.M. on KPFT 90.1 Houston, TX (Listen on the web)
Thursday
5 P.M. on WBAI New York City 99.5 FM (Listen on the web)
1 P.M. on KZYX 91.5 Mendocino County (Listen on the web)
Saturday
11 A. M. on KPFK Los Angeles 90.7 FM (Listen on the web)
Sunday
4:30 P.M. on WWUH West Hartford, CT 91.3 FM (Listen on the web)
10 P.M. on WJFF New York 90.5 FM (Listen on the web)