You probably think of your MP3s as songs, and so they are, usually. But they're also data files, and they contain a lot of information; some of it you can edit. Moo0's MP3InfoEditor lets you edit that information, including Artist, Title, Album, Year, and more, including a Comments field. It can read and write data in a huge range of text-encoding formats (the default Character Set is UTF-8; UTF-16 and UTF-16BE are available, too) and apply data to files in batches. With drag-and-drop and a Keep on Top option, it seems ideal for editing large numbers of files at once. Of course, you have to type in a lot of that data by hand, but autocomplete helps reduce the load, and the best part is, once it's done, it's done. You'll have accurate entries for album, track number, genre, and those other entries that somehow get bungled by online MP3 databases.
MP3InfoEditor's simple interface has a drop-down menu for selecting the type of operation: View & Edit, for changing data to single files, and the multiple file option, which adds check boxes to each of the data fields, allowing you to select just those you want to alter en masse and exclude the rest. It's handy for adding the year to an album without changing the rest of the metadata. Twin drop-down lists let users choose text encoding from a wide range of sets in Chinese, Turkish, Greek, Cyrillic, Hebrew, and also several Western sets. The main view displays a variety of editable fields for MP3 information: Artist, Track, Album, Title, and so on. A large button bar labeled Apply Changes starts things rolling.
Unfortunately, Vista and Windows 7 users will find that MP3InfoEditor's Drop Box doesn't work due to a Windows issue, and there's no file browser to take its place. It's in the FAQs if you're interested, but the upshot is you're out of luck. The developer is working on a fix, but until it finds one, we certainly can't recommend MP3InfoEditor anymore, at least not to Vista and Windows 7 users. If you're still using XP, give Mp3InfoEditor a try.