Ian Plant and the crew at the Dreamscapesblog are a group of talented photographers who also happen to be great writers that infuse quite a bit of humor into their posts. They produce must-read material for the landscape photographer in particular. Visual Flow is an ebook by Ian Plant and George Stocking that needed to be written for a long time. If there is a better or more comprehensive source solely dedicated to composition for landscape photography, I haven't seen it.
Composition is a big topic and I agree with Ian that it is the most challenging aspect of landscape photography to master and easily the most important. So if you're looking to add more compositional tools to your tool box you'll absolutely benefit from adding Visual Flow to your ebook library. No matter what your level of mastery might be I believe that you can always be informed by other ideas and approaches. I've followed the work of Ian and George and have appreciated their skill with composition and knew Visual Flowwould be an important read.
Photography is ultimately a two dimension artistic medium so you have to understand the elements of 2-D design as a starting point. And once you understand what those elements are, you then have to figure out how to arrange those elements in a way to express what you want to say creatively. This is composition. And it's not easy to do it well. Ian does a great job of walking you though the elements of design and deconstructing images to demonstrate each of these tools. One of the key steps in advancing your composition is to see the landscape as design elements rather than it's literal elements. Ian calls this learning to think in the abstract and it's a wonderful place to begin improving your composition.
George Stocking is a master at composing the landscape photograph and the more you understand about composition the more you begin to appreciate the well composed images of the talented photographic artist. It's easy to see George's influence on Ian's work and I think their collaboration is one of main strengths of Visual Flow. Now, you won't become a master at composition overnight, this actually takes years. But, you can speed up your learning curve by working through the image design principles and strategies that are demonstrated throughout Visual Flow. Highly recommend Visual Flow when you're ready to take your landscape composition to the next level.