The national Association of Speakers Club has a number of resources available for speakers to access.
Is public speaking limiting your career? (article on BBC website).
TED– Secrete of great public speaking.
Six Minutes Public speaking articles with tips, advice, examples, speech critiques, and book reviews.
Better Public Speaking Becoming a Confident, Compelling Speaker.
The Guardian Afraid of public speaking? This is what the experts say.
New York Times Public Speaking.