Creating Digital Landscapes

You don't need to spend thousands of dollars and hundreds of hours learning expensive graphics software to create a realistic 3D digital landscape.  My first attempt at creating a 3d image was with a program called Bryce.  With this, I created a realistic island in about 5 minutes after installing the program. 

After a while, I learned the basics of a program called Poser, which has a lot of different human and animal models that you can 'pose', hence the name.  Now, I pose a model in Poser and import that object into Bryce.  An example of this is my image of Excalibur, which uses the arm from a female Poser model to represent the Lady of the Lake. 

Bryce and Poser are good at what they do, but at some point, you're going to want to create your own models.  Wings 3D is a great tool for the job.  It's free and has just enough features to be useful, but not too many to make it unbearable to learn.  Excalibur, in my example above, was created using Wings 3D.

Another program worth mentioning is called Terragen.  Terragen is a unique program designed to create realistic landscapes, but it doesn't allow you to add and place objects directly in the scene; however, there's nothing stopping you from rendering a terragen landscape and then using it in a Photoshop composite (meaning taking 2 or more pictures and combining them to look like they were part of one - classic examples include adding bird silhouettes in a sunset picture and swapping out a boring sky with a dramatic one).

Once you've mastered these programs and are eager to learn more, there are hundreds of others to choose from.  With the mindset that free is usually better, especially during your learning curve, I'd recommend taking a look at Blender.  It's a free, full- featured modeling program good enough to create a movie.  If you have the cash and are ready to become a professional, then there are hundreds of great programs ranging from a few hundred dollars to several thousand.  In this realm are 3D Studio Max and Maya along with specialized programs for animating, modeling, texturing, lighting, etc.