http://www.rajeffsports.com/articles.php

I know people have previously referred to individual articles on Tim Rajeff's site, but I think it has been updated recently. I spent half-an-hour the other day reading and watching all of the articles, and they all seem to be great nuggets of information, delivered in a simple style.

http://www.letsflyfish.com/flyrod.htm

The "articles" section on Alistair Gowan's site - I have particularly learned from those on the subject "Fly fishing leaders"