Beyond basic tagging
When you want to do more than simply edit tags, you need to look at another solution: AppleScript. This is a scripting system built into OS X that can manipulate files and their information. Doug Adams is the reigning master of AppleScripts for iTunes, and his website, Doug's AppleScripts for iTunes has hundreds of scripts that you can use. All of these scripts are free (with a donation requested), and Doug also has a few great apps available. Here are a few of my favorite scripts:
Search-Replace Tag Text lets you find and replace text in any tags. For example, you may have a groups of albums with the word Remastered at the end of each track's name. If you want to replace it with, say, Remastered 2013, this script can make that change.
Remove n Characters from Front or Back. Let's say you want to get rid of the word Remastered after those same tracks. You can easily delete the characters, or any others, by selecting the number of characters the word uses. This works with Track, Artist, Album, Comment, Composer or Show tags. I use this script often to clean up classical music.
This Tag That Tag. This script lets you copy information from one tag and paste it, or append it, in another tag.
Albumize Selection. When you have an album that doesn't have track numbers, this script will add them in the form "1 of 10." It's much easier than manually numbering each track.
Append to Selected Tag. Add any information you want to the beginning or end of a tag, such as "Live," "Remastered," or "Demo."
Doug's site has plenty more AppleScripts. Have a browse through the Managing Track Info section for scripts that work with tags, or look at the entire site for other scripts that can help work with iTunes.
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