How do you get album artwork on iPod touch 4g?

My iPod is already Jailbroken.I tried this thing on wiki how, it said to click on advanced on the toolbar and select get album artwork.But then it said to create an iTunes account, and I don't use that stuff.I already have album artwork for some, but I want for all of them.And I have it hacked, so I won't purchase anything from iTunes.