either mess around with the camera view, or make a ramp with raise/lower tools. Look in the terrain tutorials stickied, that ramp idea is awesome, but will take you some time.
For me:
If the map size is small, I would just do a ramp.
If the map size is large, I would angle the camera, and then just angle every unit and doodad and building, etc. on the map also.
that program would so be a pain in the ass, as said in the terrain tutorial, you'd have to raise on end of the map and make columns of raise/low tool so it'd be killing. Not an easy task.
The attached tool can generate terrain from a height map.
It was made by DarkLord13
All you have to do is create an image that is mapwidth + 1 x mapheight + 1 pixels in size.
Then create a gradient (form black to white), save the image and use the tool to create the terrain.