Read "Scraping iTunes Store Metadata, Part 1: Artwork", here.
Assuming you read the first post of this series, you're well aware of my compulsive need to have my iTunes metadata identical to the iTunes Store metadata. Apple (naturally) didn't make their store particularly easy to scrape, but I found a way. Here we go.
Navigate to the album you want to copy track tags from in the iTunes Store.
Take note of the "path" to that particular album. It's located above the album artwork and looks something like Music > Rock > The Beatles
Press Command-B (⌘-B) to switch to the browse view of the iTunes Store. Not many people know about it and it's not particularly useful…except for this. It looks rather similar to the column browser in your own 'Library' tab.
Click through the columns using the 'path' you took note of earlier. ('Subgenre' is hardly ever used, just click 'All' in that column.)
Once you've drilled down to the correct artist, select your album. The bottom half of the screen will populate with the track listing in the form of 90 second previews.
Select those track previews and drag them into an empty playlist. I created one called "For Metadata."
Now you need to copy the track tags from those previews to your actual song files. To accomplish this, I turn to one of Doug's Scripts called Copy Tag Info Tracks to Tracks. It's incredibly easy to use. Install it. It's got a GUI and is pretty self explanatory, but I'll walk you through it, anyway.
Select (highlight) the group of previews inside the "For Metadata" playlist (sorted in the correct album order…that matters)
Launch the script. (When installed it will appear in a script menu in the iTunes menu bar.)
Check all the boxes except for 'Artwork'.
Click "Proceed" in the script.
Select (highlight) the target group of tracks. Again, double check sort order.
Click "Proceed" again, and you're done.
If everything worked properly, your iTunes files should have identical metadata to those previews from the store. Now:
Return to the 'For Metadata' playlist.
Select the previews you dragged there from the iTunes Store.
Hold the 'Option' key and press 'Delete'. The option modifier deletes the selected files from the entire library, not just the current playlist. There's no reason to keep a bunch of 90 second previews in your library.
An "Are you sure?" dialog will pop up. Go ahead and click 'Delete items'.
And that's all there is to it. Combined with my artwork scraping bookmarklet I detailed yesterday, you've got all the tools you need to edit your metadata to match the iTunes Store.