MediaMonkey is able to search online for album art, but more often than not the first result is not the best one. If you don't hand-pick the album art that you want to use, and you instead have a script automatically pick art for each file, you probably won't like the results.

I need artwork for 17000 files automaticly and can't find a vry simple tag that help me to save me time cus 17000 are big files to do evey single file and take one by one is a kill and need genre and year and title and artist .