Define image for artist?

Hi,

Has anyone figured out how to add or change an image for an artist in the left hand column of the 'Artists' view please? It seems to have retained the image I defined in Grid view in version 10.x, but after managing to accidentally delete all 1049 songs defined as Various Artists just now (be warned - deleting a single item in Artists view is seemingly not possible) and then having to re-import them all from the trash, the left hand column only shows the iTunes icon now.