ello I've just got a zen (wooo) and it organises music based on the id3, I've never had a player which does that and so I've never worried about id3 too much. As a result most of my music either has highly varying id3 or none at all. Is there a program/wmp plug-in/whatever where I can select a group of files (basically all of the songs on the album) then tell it "those tracks are this album" and it'll check against a database and add the id3 tags to the files automatically? I'd do it manually but with 10gb or so of music to sort through I'd rather not.
If you want something neat and fast then try JJ MP3 renamer. "CD database to ID3 tag lets you download ID3 tag information from the Allmusic.com CD database." It's free and works nicely. I used to use JJ all the time for writing tags, but now I just use it to clear tags from downloaded mp3s before I import them into iTunes. iTunes is pretty good with tags, but it's a bit of a resource monster.