Where did “Find Album Artwork” go

In many cases, improper tagging causes the files to go weird places. I suggest you create a smart playlist that shows you “new added” stuff:

I usually have the same problem with mp3 with dubious tagging.

I had the exact same problem several times in the last three years (with an iPhone 3G, an iPhone 4 & an iPod touch).

I always solved it this way :

1. disable music syncing for the device (uncheck everything in the "music" tab)
2. sync the device at least two times
3. enable music syncing
4. sync again

I usually divide steps 3 & 4 in smaller steps. I begin by syncing a few artists to check everything is fine before syncing all the music I want on my device.

I hope this will work for you.