Does any one know how to design a the tile-based map of 3D type but 2D Screen just like the map of AGE OF KINGDOM (AOE 2)? Should it base on the D3D?

AoE is a tile based game (to the best of my knowledge). It works similarly to games such as StarCraft and Command and Conquer, in that it specifies its map using tiles.

You can use maybe a hexagonal grid, or regular quadrilaterals, and simply specify each cell in your map as a certain terrain type. This allows for the various textures, and illusion of height. I doubt very much if AoE uses D3D to simulate the height, it is far more probable that it simple uses a shaded texture to give that illusion.

you will want to look at the isometric/hexagonal section of the forum/programming refrence thats what you want, isometric is for the diablo semi 3d look and hex is more for top down view, and it can use D3D if you want, the game Im working on is an iso rendered in d3d but it could be done in 2d

to design it use the flocking princaple so
if theres a tree nearby then theres likely to be a tree here (everything is in groups) check out empires at my page for an example of this thats is if i aint changed it . http://members.xoom.com/myBollux/home.html