Essays, Articles Lessons & Interviews from the World Haiku Club & World Haiku Review
http://www.worldhaikuclub.org/pages/resources_renku_whcwhr.html
Renku Home - Williams Higginson
http://renku.home.att.net/index.html
Several articles, links, bibliography. An introduction to haiku, advices for writing, rules, a practical guide for composition.
Aha! Poetry - Jane Reichhold
http://www.ahapoetry.com/renga.htm
Information, definition of renga, articles, examples. Structures of seasonal renga kasen
Compilation of terms related to the renga: see the Glossary page (jan 09th,05)
In French :
Une définition du renku (A. Duhaime)