Edit: I was wrong. After actually reading the page I linked to, you must install it from the CD. (Oops.) How annoying. I can't help you with the CD and it's probably not legal for anyone else to provide a copy, either.
You can download the Media Player update for upgraded iPAQs from
this page at Microsoft without needing a copy of the upgrade CD.
By the way, welcome to Pocket PC Thoughts!