I hate when I download MP3's (which I of course have copyright permission for ;) and they don't have ID3 tag info. Also, as I am a unix geek, I hate anything I can't script at a command line. Therefore, I had to find a command-line tool to edit and display ID3 info. In my travels, I finally came upon id3tool. Admittedly, there probably are a lot of other tools, but this one was pretty darn easy. I downloaded the source, and used the standard ./configure, make, sudo make install and had it running in less than a minute (I have the latest Dev Tools installed, BTW). I'll e-mail the author and see if he's OK with me posting a binary to my website for this; if so and if anyone's interested, please make it known in the comments here.
Anyway, this, for me was perfect. Now I can shell script batch ID3 updating (perfect for when I have a bunch with the same artist/album). This has made my life a LOT easier.
Let me know if anyone wants an example of how to shell script using this tool. It's definitely not a "newbie" process, as the scripts I use require knowledge of sed, awk, cut and basic bash scripting precepts. But, even without scripting, this tool is a great, simple command-line way of fixing ID3 info.
Mac OS X Hints
http://hints.macworld.com/article.php?story=20030805003033280