Firstly, complete credit to tijs for the original plugin, allowing you to display your recent tracks on your wordpress blog. I wanted a weekly artists option, and noticed some other people were after the same, so I modified a few parts and decided to make it available :)

You can download it here: lastfm_artists.phps

Installing:

1. Save the file, and change .phps to .php
2. Upload to your plugins folder.
3. Call the weekly_artists function (as explained in the plugin) somewhere in your template (for example, sidebar.php).

Hope this helps some people! :)