See this resource list of free/paid software:
  • 3ders resources - 3ders has a comprehensive list of free and paid 3D printing software available. 
General CAD & 3D Software
  • SolidWorks
  • SketchUP
  • Tinkercad
  • Rhino 3D
  • OpenSCAD
  • Blender
  • Mol3D
  • Wings3D
  • Scupltris
  • Autodesk 123D
  • LightWave
  • AutoCAD
  • Autodesk Inventor
  • Maya
  • 3ds Max
  • Mudbox
  • Creo
  • ZBrush
  • Mathematica
  • Matlab
Software for dealing with STL files: 

  • Meshlab
  • Skeinforge
  • Slic3r
  • Redsnapper
  • Cura
  • ConvertSTL
  • IVCON
  • Creation Workshop
  • netfabb Studio
  • Kisslicer
  • MeshMixer
Software for sending G-Code to the 3D printer

  • SD Card
  • MakerWare
  • ReplicatorG
  • Repetier-Host
  • OctoPrint
  • Pronterface (Printrun)
  • RepRap Host Software
  • RepSnapper
  • RebRep
  • send.py (bundled with SkeinForge)
  • YARRH (Yet Another RepRap Host)
  • X2SW
  • G-Code-utils
  • G-Code Simulator & Printer
  • EMCRepRap
  • CNCGcodeController