I just figured it out. (Because it's very simple and because I'm whatever the opposite of gifted is, this took me several years.)
Here's how:
2. Look for a little down-arrow-triangle symbol to the right of the listing for the song. Click on that.
4. Paste your new link into your blog post, or email or Tweet or Facebook-thingee.
5. Stand in front of a mirror for a few minutes, practicing your look of competent insouciance in preparation for all the praise you'll get from impressed friends and co-workers.