From: "DoLL" <jbdoll AT hanmail DOT net>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Finding the Dang MS PLATFORM SDK
Date: Mon, 6 Sep 1999 21:46:34 +0900
Organization: System Engineering Research Institute (SERI)
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Message-ID: <7r0d6s$i0d$1@green.kreonet.re.kr>
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To: djgpp AT delorie DOT com
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Reply-To: djgpp AT delorie DOT com

It was THERE!
and the name was IBLDENV.EXE as rsxntdj.hlp says.

But, MS moved the site.
It's now at http://msdn.microsoft.com/developer/sdk/
There's  "Download the Platform SDK " link.

Good Luck.