Microformats.org - The official microformats site. Contains the development wiki, mailing-list information and scripts to create the major microformats.
Alex Faaborg: Microformats A series of blog posts giving an introduction to microformats and how these are to be handled in Firefox 3. http://blog.mozilla.com/faaborg/2006/12/11/microformats-part-0-introduction/
hCard Validator Tool which validates microformatted hCards against the current specification. Also provides helpful and educational hints about hCards. http://hcard.geekhood.net/
hResume Project WordPress plugin to display a resume marked up in a hResume microformat. http://hresume.weblogswork.com/?page_id=3
Microformats Bookmarklet A browser bookmarklet created for detecting, displaying, and downloading microformats. http://leftlogic.com/lounge/articles/microformats_bookmarklet/
Oomph Microformats Toolkit For web developers, designers and users, making it easier to create, consume, and style Microformats. http://visitmix.com/Lab/oomph/
Operator Firefox extension to handle microformats from within your Firefox. Contains intro, changelog, and user comments. https://addons.mozilla.org/firefox/4106/
Planet Microformats An RSS aggregation website, sharing information on all things microformats. http://planetmicroformats.com/
Wikipedia: Microformat Explanation of microformats with examples of its usage. http://en.wikipedia.org/wiki/Microformat
XML.com: What Are Microformats Micah Dubinko asks what microformats are and whether they are here to stay. http://www.xml.com/pub/a/2005/03/23/deviant.html
Microformats: What, How, and Why Overview of what Microformats are, how to use them, and why website owners should use them. (November 3, 2009) http://www.vanseodesign.com/web-design/microformats-what-how-why/
Microformats for Business Owners An explanation of the practical benefits that microformats can bring to a business and its customers. (March 13, 2009) http://www.clagnut.com/blog/2244/
hAccessibility Article by Bruce Lawson and James Craig, raising accessibility issues with the use of some microformats, and specifically the abbr design pattern. (April 27, 2007) http://www.webstandards.org/2007/04/27/haccessibility/