NEED HELP WORKING ITUNES

ok..so..iTunes is good for some stuff...but

how do you go onto the internet, like to search for an album cover (to add to album artwork for an iPod) and make it as your album artwork?

ex-google pictures, search for an album. how do I get that as album artwork? I know that you can get artwork if you are logged in, but most of the time iTunes stinks at getting the artwork. thanks

basicly i want to be able to know how to take pics from the internet and make them my album artwork. I know there is a way-I just dont know how.