Hi Max,You would need more than a few GPS points to create a model. ArcGIS offers the options to create raster surfaces by interpolating points or TINs by triangulating between 3D points or nodes. You can add your points from excel to ArcGIS and create a 3D point feature class. Using the Add XY Data tool. Documentation for this tool is below.Adding x,y coordinate data as a layerhttp://resources.arcgis.com/en/help/main/10.1/index.html#//00s50000001z000000Here is some options for creating multipatches and elevation surfaces you may want to look at. Making a large-scale 3D Map: Part 2 (Blog on how to use the extrusion tool in ArcScene)http://blogs.esri.com/esri/arcgis/2012/01/10/making-a-large-scale-3d-map-part-2/Understanding interpolation analysishttp://resources.arcgis.com/en/help/main/10.1/index.html#/Understanding_interpolation_analysis/00q90...What is a TIN surface ?http://resources.arcgis.com/en/help/main/10.1/index.html#//006000000001000000Best wishes,Carrie