You’ll have to forgive the “2006” date on these. The music is beautiful, so I’m going to post them despite it being 2009.
For more on the O Antiphons, you can go in my way-back machine to these posts. (In the future, I will use the label that I added specifically for these Antiphons.) You can also read some more on them at Julie’s blog, Happy Catholic. (I recommend her blog, anyway!)