Open Mind with Bill Jenkins is the best alternative to Art I've found so far. The radio show was out of KABC (IIRC?) in Los Angeles. It was on in the early 80's. You can find the torrent file for the show online. Problem is: There are only a few episodes (a dozen or so) so when you're through them you're through them. Art's shtick, to me, is really half Art doing a sort of P.T. Barnum impression and half Bill Jenkins. You should check it out.
I wish James Randi would do a podcast, although he might come off as being too harsh on his subjects, but I don't think he has one.