Check out this code project article, it's a little more in depth than the blog post you mentioned.
http://www.codeproject.com/KB/trace/minememoryreader.aspx
Edit
And this article, although not about minesweeper directly, gives you a good step by step guide on hunting through memory using WinDbg:
http://www.codingthewheel.com/archives/extracting-hidden-text-with-windbg
Edit 2
Again, this isn't about minesweeper, but it has definitely given me some food for thought for my memory debugging, there's a wealth of tutorials here:
http://memoryhacking.com/forums/index.php
Also, download CheatEngine (mentioned by Nick D.) and work through the tutorial it comes with.
http://rads.stackoverflow.com/amzn/click/0764574817
http://stackoverflow.com/questions/931257/how-can-i-find-the-data-structure-that-represents-mine-layout-of-minesweeper-in-memory#1160282
http://www.subversity.net/reversing/hacking-minesweeper
Code project
http://www.codeproject.com/KB/trace/minememoryreader.aspx
http://www.amazon.com/dp/0764574817/?tag=stackoverfl08-20
http://www.codingthewheel.com/archives/extracting-hidden-text-with-windbg
http://memoryhacking.com/forums/index.php
http://angusj.com/resourcehacker/
http://www.cheatengine.org/aboutce.php