I have a HTPC and wish to use my original XBOX as a media extender. Where the heck can I purchase the media extender kit or atleast get the software from?

The original microsoft product only runs on the xp home theater edition. If you are using something else on your htpc, you can't use it. I don't think it will be asy to find it, as it has never been very popular. As far as I remember, you can use the software with the original dvd playback remote control, so you will need just the software, not the whole kit.

The xbmc dashboard for a modded xbox is a full featured media center. It can play media from a smb share and from upnp servers. Just check T3CH for the latest versions, or check the usual places for the latest stable build. It might furfill pretty much all your needs.

regards.