The best way to learn from Trey is, of course, in person. Each year he runs a selection of workshops around the world such as a 5-day spring (October in New Zealand) event. You can see all available workshops here.
In addition to this Trey offers a number of video tutorials covering Aurora HDR, Lightroom, Photomatix and more. View them here.
Also keep an eye out for free events such as photo walks. The best way to do this is to subscribe to our newsletter.
And finally, Trey's written HDR tutorial is always available, and free! Read it here.