The textures are blended by vertex-colors on the terrain mesh. The white lines for the parking-lots are usally decals. Decals are polygon-meshes that are on top of the actual geometry.
Would be better if the question changed month to month. Or pulled from a database of questions that kept track of usage (to keep people from passing on the answers).
Are you just looking on how to load an HLSL file in Maya ? Because the values and general usage of the shader should be the same as older videos for Max.