I record Cartalk each week and use to do it on Radio Shack Concerttape t120's the cheap ones. They work fine and are still avilable. But a few years ago I switched to a computer based mp3 recorder and plug my radio headphone plug into the microphone plug on the computer sound card.
http://www.freedownloadscenter.com/M..._Recorder.html its called 3D mp3 sound recorder. It looks just like a tape player, and you can adjust the audio quality all the way from very poor voice, up tp above CD quality. My 1 hour show takes up 19MB. 48KB bit rate. You can then play it back onto a tape recorder, make a few tapes at a time to use on your low-tech stuff, re-use the tapes you have every few weeks, and always have the mp3's on your computer. (keep backups) It will save you tons of cash.