I find myself using these resources over and over when I work with HTML and CSS, so here they are:
* "HTML 4.0 Entities for Symbols and Greek Letters":http://htmlhelp.com/reference/html40/entities/symbols.html
* "HTML Tutorial":http://www.w3schools.com/html/
* "CSS Tutorial":http://www.w3schools.com/css/
* "Formatting a Definition List < CSS":http://www.the-art-of-web.com/css/format-dl/
Also, I've discovered that embedding @h2@ tags in @dt@ is _not_ allowed in strict XHTML 1.1.
UPDATE (22 November 2011):
* "HTML Entity Names":http://www.fileformat.info/format/w3c/htmlentity.htm
* "fileformat.info":http://www.fileformat.info/
* "UTF-8-demo.txt":http://www.cl.cam.ac.uk/~mgk25/ucs/examples/UTF-8-demo.txt
* "UTF-8 and Unicode FAQ for Unix/Linux":http://www.cl.cam.ac.uk/~mgk25/unicode.html