Fury points to a new (old) way to get old music onto new formats: the PlusDeck 2C, a cassette deck in a 5.25″ PC drive form factor. It’s Windows only and would make more sense as a USB (2.0) drive, but for those of us that are stuck with some music that is only on cassette it’s not bad.
I found another solution, too, which I actually ordered: the now relatively venerable Griffin iMic. This is a USB connection on one side, standard audio in jacks that can accept either line-level input from phonographs or normal output from another audio device, like a cassette deck, on the other. This means that I can get copies of some of that obscure vinyl in digital format, finally. I’m thinking that parts of the spoken word record of Kemp Malone reading Beowulf is a good first start (though perhaps not all four hours). The bad news, of course, is that the iMic is so venerable it is starting to be unavailable, so grab it at Amazon while you can, even with a four to six week lead time.