In AutoCAD you could use the 3D face command to build a set of planes which connect your contour lines. Pick your points in a counter clockwise direction so that when you import into 3dS max any texture will come in on the top facing plane.

An alternative way to do this is to use the "add location" feature in sketchup. This allows you to select any area in the world and get terrain data. You can then export the 3D model as a .3ds file and you will have a mesh that you can manipulate.

I don't have the programs in front of me, but going from memory here:

It is actually really simple in 3ds max... import your geometry (topo lines) and select them go to the create panel on the right (or whereever it is you moved it), make sure that the geometry button is selected in the create tab. Choose compund object and click terrain on the roll out. Nice thing is you can export it to almost anything and make it either solid or just surface. You can even make a gradient height map.

in sketchup, you can import the cad geometry and use the sandbox tool "from contours" to create a surface from the selected lines, but it will take longer if it is a big file.

Revit is pretty easy as well. If you want to play with revit, the revitkid has great tuts for this. revit detail is also a good site for revit related learning. The benefit to using revit would be that you can model directly on the site to get your plans, elevations, etc. plus the render engine is mental ray so it works pretty nice if you have the machine and the time.