PC migration. One-step Album art import from WMP library?.

Hi. I'm a long term unix user at work, and I've tolerated windows for some years for home use. Seeking to escape windows finally at the prospect of vista, I weighed up Mac or OpenSuse/Ubuntu or similar and went for Mac.

All my data is on a readyNAS NV+. I have 20Gb of legitimate music, painstakingly loaded over the years using audiograbber and LAME encoder into a WMP file structure. Artist / album name / tracks.

I have pointed iTunes at this network library and the music plays (though folders are ignored and everything appears as one flat structure). But, all the album art hasn't transferred. Googling hasn't revealed a one-step solution.

I know I can right-click and say "get album art", but I don't want to do this 1000 times when I know any computer must be smarter than that. I can browse to the album folder in finder, grab the AlbumArt_{xxxxxxx}_Large.jpg and drag and drop this into itunes bottom-left "drag album artwork here" section and this works perfectly. But again, I don't want to do this 1000 times.

Thoughts welcomed.
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