Adding artwork in iTunes? How?

[c0sie]

I bought my first ever iPod afew months ago, downloaded iTunes, copied all my current stash of mp3's into iTunes/my iPod, and have even used iTunes to copy music from CD into my library but no matter what I try, ive pressed al the Add Artwork buttons and even been to the Apple support pages I cannot get any artwork to be downloaded or added at all.

I have a valid iTunes store account, but even with that I cant figure it out.

Any technical wizards able to help??