What most naturally follows?

How to have a perfect itunes library
Start with your old itunes library.
Look and see if you have any albums missing, if so google the artist, wikipedia usually has the complete discography, and fix your albums with proper capitalization. This is key!
Find album artwork.
This can be challenging at first but after you get the hang of it it is easy and moves quickly, simply copy and paste the album title into google images. A wide variety should pop up, if not, keep searching.