From Microsoft Downloads
"Windows Media Player 11 offers great new ways to store and enjoy all of your digital media. It’s easier than ever to access all of your music, video, pictures, and recorded TV on your computer. Play it, view it, organize it, and sync it to a portable device for enjoying on the go, or share with devices around your home – all from one place. Windows Media Player 11 is designed to work with all versions of Windows XP with Service Pack 2, including Windows XP Home Edition N and Windows XP Professional N."
Update: You can download the x64 build here
Thanks again to Volkan for the tip.