Open iTunes and then find the iTunes "Preferences" feature. For Mac users, simply open iTunes and then choose "Preferences" from the top toolbar. For Windows users, choose "Edit" and then click "Preferences."
Click the word "Store" from the tabs that appear, and make sure the box is checked next to "Automatically download missing album artwork." Now click "OK." Checking this option will ensure that iTunes finds artwork for any imported songs and albums you may download in the future.
Return to your song library and find the artwork for all of your albums at once by clicking "Advanced" and then "Get Album Artwork" from the iTunes navigation toolbar. An alert message may pop up explaining that songs with missing album artwork will be sent to iTunes. Agree to this prompt and you will see a message that iTunes is "Processing Album Artwork." When this is finished, you may receive a message that states some artwork could not be found for specific albums.
Make sure you have the most up-to-date version of iTunes by going to the toolbar, clicking "Help" and then selecting "Check for Updates." If a prompt appears asking you to download a newer version of iTunes, you should agree to it. When the new update is finished, it should include all artwork already found or imported in the previous version of iTunes.
Change your visual settings on iTunes in order to see your album artwork. If you cannot see artwork when playings songs click on "View" and then "Show Artwork" on a Mac, or use the shortcut "Ctrl + G" on a PC.
Include all relevant metadata when importing any songs or albums into iTunes in the future. Do this by right-clicking on a track and selecting "Get Info." Under the info tab fill out all fields, including name, artist, year, track number and album. Following these steps will help iTunes to acquire album art for your music.