hello pixelone,
Your ocean avi file looks great, as for the mountains in the picture above the detail is low due to distance so i wouldn't really bother modelling trees or rocks.
http://www.newtek.com/products/light...nts/index.html
http://www.newtek.com/products/light...landscape.html
The above are some links from newtek for terrain modelling that should help you. With the ocean made you will find the rest quite easy as the detail required is low.
Hope this helps you at least a little.
OzWOlf