   creating a 3d world!!....HELP!
  Hi all,I can be safely called a beginner in game development using directx9 in c++.I have developed 3 3d games...the last one being a plane fighter game.I am ok with all the physics,i have developed my particle engine and am learning more and more about 3d effects like making skyboxes etc.Till date i take game projects that involve least requirements of 3d models as i dont have any and use the directxSDK samples.I want to ask one thing....how do i create a 3d world...like a 3d mountain biking terrain...so that i know the co-ordinates of each and every point.I dont know 3d modelling and the models i download....i dont know the method to extract the vertex buffer information.This is topping me from being creative and undertaking complex game ideas.So please either tell me a solution to this problem...or if you could suggest some nice game which i can make without it!!!!Thanks a ton!!i m stuck!   