There is the original offering from MS which was IBuySpy Portal.
Then there was Walker's re-factored version of that which was called IBuySpy Workshop, which has morphed into DotNetNuke.
MS is now offering something similar to IBuySpy Portal in their quick-start kits but it is no longer called IBuySpy, I believe. See
http://www.asp.net/Default.aspx?tabindex=8&tabid=47.
If what you are really looking for is IBuySpy Workshop from Sean Walker circa Christmas 2002 and months following, I have no idea.