I've recently come across some topics and questions regarding the display of Album Art in the N91 Music Player. Depending on where you get your music from the album art isn't attached to a file... unless of course its downloaded from iTunes, but that won't help us here.
I haven't found a more simple method but I will share my solution. First of all, I get my music from AllTunes.com (the guys at AAS rave about this). I usually just copy the image of the album and save it to my laptop. Once I've downloaded the album using Nokia's Music Manager I can now add my album art.
As you can see from the above images the process really isn't as hard as you think. Start by first finding your album image and then sending it to the phone. Store it in your gallery.
Next, open your Music Player and select the artist. Select the Album or Artist that you wish to add the album art to. Select options and go to Album Art. Select options again and go to change. This will then take you to your gallery where your image is stored. Select the image and viola' your done!
This is the method that I use but by all means, if there is an easier way please feel free to share.
Via [Darla Mack]