As you enter Artists on a product or track, Central will look up each Artist at Apple and return matches based on the text entered. To view these matches, simply click the Apple logo next to each Artist's Role.
If no matches are returned - for instance, if this is the artist's first release - then your only choice will be to create a new artist. If chosen, this will request a new Apple Artist ID and attach it to the artist for delivery to Apple.
If one or more matches are returned - for instance, if there are multiple artists in the real world with the same name, or there have been multiple artist pages created in the past for the same artist - you can click each one to view the artist page at Apple and determine which one is correct.
Although currently optional, it is highly recommended that you take the time to choose the correct artist page for every artist you enter. For older content or recent new Submissions for which you have not made the choice, you can manage it in Change Requests as well.
If you need to move an artist from an incorrect artist page at Apple to its correct page, simply create a Change Request and use the Apple Artist ID feature exactly as you would in Submissions.
The artist will already be present on the product and Central will automatically look up any matches at Apple. Make your selection, submit your Change Request, and the change will be delivered to Apple as an ordinary metadata update. The end result will be the product or track in question being moved to the appropriate artist page at Apple.