Nine No's of Dialogue from diy MFA is an excellent examination of how we can strengthen our dialogue.
Harness the Power of Words on the Finding Bliss site discusses the intentional and clever use of words to enrich our writing.
Treasures in the Attic is the latest in the Making the Most of Ideas series of articles by David B Coe on the Magical Words site.
How Stephen King Writes Imagery from Galleycat offers some excellent writing advice from one of my writing favourites.
Stay On Target: When is a Subplot Leading You Astray? from The Other Side of the Story talks about the value and danger of subplots.