Mary Buckham.Signing up for any workshop Mary runs will be worth the investment of time and money. I particularly recommend her Plotting With Mythic Structure.
Alicia Rasley. When I started writing I took a number of Alicia's workshops, and they were all excellent.
Leigh Michaels. My first taste of writing romance was on a free course I took at Barnes & Noble University online with Leigh. I then took her two romance writing courses at Gotham Writers' Workshops. I highly recommend Leigh's courses to any beginner as she gives a fantastic grounding in a supportive environment.
Tami Cowden. Tami runs a number of good workshops. The one I found most useful was her workshop on Archetypes.
Laurie Campbell. Laurie is a lovely lady who I had the pleasure of meeting in 2005 when she came to England to give workshops at the Romantic Novelists' Association conference. She runs a number of excellent courses. My favorite is The Selling Synopsis.
Margie Lawson. Margie is a powerhouse of information. I can highly recommend both her Empowering Character's Emotion and EDIT'S system courses.
Earthly Charms run a number of online courses each month. They provide a varied program with courses covering general writing craft and more specific genre interests.
Below are listed the best of the books I've read on writing craft and used for research. I will add to the list as I find more I can recommend.
Writing Craft Books:
Freefall. Writing Without a Parachute by Barbara Turner-Vesselago
Wild Mind, Living the Writer's Life by Natalie Goldberg.
Creating Romantic Characters by Leigh Michaels.
Writing The Romance Novel by Leigh Michaels. (Leigh gives a wonderful grounding in the basics of romance writing for the beginner.) www.leighmichaels.com
Goal, Motivation & Conflict by Debra Dixon. (A must have book for all writers.)
Heroes & Heroines, Sixteen Master Archetypes by Tami Cowden, Caro LaFever and Sue Viders. (I think instinctively we all understand character archetypes on an unconscious level. This is a great book for bringing that understanding into consciousness.)
Characters & Viewpoint by Orson Scott Card. (Excellent and accessible.)
Scene & Structure by Jack Bickham. (Good grounding in the structure of commercial fiction.)
How To Write A Damn Good Novel by James N. Frey
Solutions for Writers by Sol Stein
Solutions for Novelists by Sol Stein
The Plot Thickens by Noah Lukeman
Techniques of the Selling Writer by Dwight V. Swain
Story by Robert McKee
The Power of Point of View by Alicia Rasley. (Available on her website http://www.sff.net/people/alicia/)
The Comic Toolbox by John Vorhaus. (An excellent section on plotting that can be applied to any type of story.)
The Dreaded Synopsis, A Writing & Plotting Guide by Elizabeth Sinclair.(I am hugely indebted to Elizabeth for my copy of her book. As I'm in England, we couldn't work out a way for me to pay her for the book--so she sent me a copy as a gift!)
Writing the Breakout Novel by Donald Maass. (Excellent advice for writers with a little experience under their belt. He also has a workbook that covers similar ground.)
Dangerous Men and Adventurous Women edited by Jayne Ann Krentz. (Thought provoking essays by notable romance writers on the appeal of the romance novel.)
The Writer's Journey by Christopher Vogler. (A wonderful book that in conjunction with Mary Buckham's plotting course has given me a through understanding of plot. I highly recommend this book.)
The Art of Punctuation by Noah Lukeman.
Eats Shoots & Leaves by Lynne Truss. (Hilarious and educational!)
501 English Verbs by Thomas R. Beyer. (Okay, I'm obsessive. Useful for me in checking up the different British and American usages that drive me nuts.)
The Deluxe Transitive Vampire, The Ultimate Handbook of Grammar for the Innocent, the Eager, and the Doomed by Karen Elizabeth Gordon. (Grammar for those who walk on the dark side.)
The New Well-Tempered Sentence by Karen Elizabeth Gordon.
The Elements of Style by Strunk and White. (Okay, this is a given, but I put it in anyway.)
Revising Fiction. A Handbook For Writers by David Madden.
Self-Editing For Fiction Writers by Renni Browne and Dave King.
Novel & Short Story Writers' Market.
Divided by a Common Language by Christopher Davies. (For anyone interested in the differences between British English and American English.)
Other Research Books:
How To Write Science Fiction & Fantasy by Orson Scott Card.
The Illustrated Encyclopedia of Fairies by Anna Franklin.
Green Witchcraft, Folk Magic, Fairy Lore & Herb Craft by Ann Moura.
The Complete Guide to Fairies & Magical Beings by Cassandra Eason.
Working With Angels, Fairies & Nature Spirits by William Bloom.
The Encyclopedia of Ghosts and Spirits by Rosemary Ellen Guiley.
The Element Encyclopedia of 20,000 Dreams by Theresa Cheung.
The Element Encyclopedia of 5,000 Spells by Judika Illes.
The Element Encyclopedia of Witch Craft by Judika Illes.
The Element Encyclopedia of Secret Societies and Hidden History by John Michael Greer.
The Element Encyclopedia of Magical Creatures by John & Caitlin Mathews.
The Element Encyclopedia of the Psychic World by Theresa Cheung.
Vampires, The Occult Truth by Konstantinos.
Summoning Spirits, The Art of Magical Evocation by Konstantinos.
The New Quantum Universe By Tony Hey and Patrick Walters.
Tarot Plain and Simple by Anthony Louis.
Learning the Tarot by Joan Bunning.
Tarot for Your Self by Mary K. Greer.
The Crystal Bible by Judy Hall. (The best crystal book I've discovered.)
The Family Health Guide to Homeopathy by Doctor Barry Rose.
Are You My Type, Am I Yours? Relationships Made Easy Through the Enneagram by Renee Baron & Elizabeth Wagele.
The Enneagram Made Easy, Discover the 9 Types of People by Renee Baron & Elizabeth Wagele
The Enneagram in Love & Work by Helen Palmer.
Type Talk. The 16 Personality Types That Determine How We Live, Love and Work by Otto Kroeger and Janet M. Thuesen. (Based on the Myers-Briggs personality indicator.)
Blame Your Planet. A Wicked Astrological Tour Through the Darkside Zodiac by Stella Hyde. (Great look at the bad points of all the signs!)
Love Signs by Linda Goodman.
Sun Signs by Linda Goodman.
You Just Don't Understand. Women and Men in Conversation by Deborah Tannen. (The reason why men and women communicate differently.)
Last but not Least:
Tarot of the Cat People. Designed by Karen Kuykendall.
The Robin Wood Tarot.
Art Nouveau Tarot by Matt Myers. (My favorite Tarot cards. Jewel bright colors depicting the artist's beautiful friends in a set based on the traditional Rider Waite designs.)
Archetype Cards by Caroline Myss. (Useful to get the brain churning for character development.)