imported post
Best Buys, or online.
Many cell phones will record voice memos too--some are better than others though, and some of the software to do this on smartphones will stop recording if a call or text message comes in...
You can get a good-quality digital voice recorder for under $50 if you shop around. Best Buys should have them on sale soon for the holidays...
Look at the SanDisk Sansa if you're on a budget. Their "View" model has 8gigs of memory, which can provide a whole day's worth of recording. and it can be had for under $60. The smaller Sansa's (2gig, 4 gig) can be had for even less, and they are small, discreet, and work with most computers for downloading audio files.
If you have deep pockets and want to go higher quality, the Olympus digital recorders are purpose-designed for recording speech, (they are not just MP3 players that also record, like the Sansa), have better mics, and are small and have great battery life. They also cost between $100 and $250, depending on the model.
If cost is not an issue, and you want production-quality sound, look at Tascam. They make a model called the DR-1 that uses SD cards (and can take up to a 32gig card) and can record a number of formats, from MP3 to true CD-quality. Of course, they retail for about $300, and are a little bigger than the old, big PalmPilots...
If you have a Mac, your choices are a little more limited, because some of the companies (Sony, Panasonic, etc) are notoriously Mac-unfriendly. so getting the files off your recorder and into a computer can be tricky (if not nearly impossible). But The Sansa is accessable from a Mac, although it does not include software for file transfer and is not iTunes compliant.
Good luck!