You might have noticed the large-size artwork I added to the top of my music post this week. If you are ever looking for proper-sized or high-resolution artwork for your music collection, Ben Dodson has written a really cool little web app using the iTunes Search API to find the album artwork you need.
I use this tool to find artwork for albums that iTunes tends to miss in the automatic process, as well as for TV shows I have on DVD that I’ve ripped to my iTunes library (so the artwork looks correct on an Apple TV).
Check it out and search for something. The only downside is that stuff that’s not on the iTunes Store won’t return anything, but that’s rarely a problem in my experience.