OK, I’ve figured it out. I looked through a lot of trash and ended up with two really simple programs: Juice for downloading podcasts to your computer, and Shuffler for transferring from computer to MP3 player, assuming your MP3 player works like mine does (that is, it creates a drive letter, which is pretty typical). PodcatcherMatrix looks like a good site too, and includes all of the podcatchers I evaluated, plus more.