Again, like all writer wanna-bees, I have been to a multitude of writers trainings. Some better than others. The ones I have the hardest time with are the ones who seem to think you're just there to fan them.
The author that stands out above all others in terms of large amounts of practical, usable tips is Cherry Adair. To see upcoming places where Cherry will be appearing enter the site and click on Events and Appearences. You won't be disappointed.