This one was rather elusive. I finally found the solution in a side window that shows up when viewing a PDF file within Google Docs, i.e. https://docs.google.com/leaf?id=0B9EbcIuh6W3vOTc5ODRlOTMtNmM3ZS00OGQzLTkyM2Et…

In the right sidebar, there’s a little window with embed code that has HTML code like this:

Ishot-1010201

So if you’ve got a PDF file you’ve uploaded to Google Docs, and can’t get it to show using the Google Docs Viewer generator at http://docs.google.com/viewer . The code you’d use is like this — note: replace srcid with your PDF document’s ID.

Ishot-1010202

That should do it. You can change the width and height as you’d like.

[aside: wasn’t able to figure out how to post HTML code in a Posterous post, so had to use images, which means you’ll have to carefully type out the cryptic embed codes, sorry]