Free Download
For AutoCAD 2010, 2011, and 2012 Systems*
ArcGIS for AutoCAD 300 is compatible with ArcGIS for Server for Java and the Microsoft .NET framework (see all system requirements). ArcGIS for AutoCAD is also compatible with ArcGIS Online.
Read the ArcGIS for AutoCAD installation instructions for assistance in the download process.
*Support for AutoCAD 2013 coming soon