xarch AutoCAD Info and Tools - A resource for AutoCAD developers, including an AutoLISP standard library and the AutoLISP FAQ, as well as code examples in AutoLISP, ADS, and ARX. Visitors can add information in an AutoCAD Wiki.
ObjectDCL - An interactive replacement of the DCL language for developing dialog boxes within AutoCAD, sold online.
AutoCAD Developers Group Europe - A non-profit association of software developers who are working on applications around AutoCAD.
Py_acad - A free software module that makes it possible to extend AutoCAD with the Python programming language, in a similar way as with AutoLISP.
AfraLisp - Dedicated to the study of AutoLisp and VBA together with AutoCAD, including tutorials about both languages.
AJaX - the AutoCAD/Java eXtension - An open source project to integrate a Java2 VM into AutoCAD and to provide the necessary interfaces and class libraries.
Jimmy B's - Free source code and ideas for AutoCAD. AutoLISP, and VBA [only the HTML based menu works].
OpenDWG Alliance - An association of CAD customers and vendors committed to promoting Autodesk's AutoCAD DWG drawing file format as an open, industry-standard format for the exchange of CAD drawings.
DCL Code Generator - An integrated development environment helping in the programming of DCL dialogue boxes for AutoCAD.
Ransen's ObjectARX Course - A multimedia based tutorial on programming ObjectARX on CD-ROM, with three of 20 chapters downloadable as a demo.
Icombiz co., Ltd. - The IcomTools add extendability through the AutoLISP, DCL, ADS, and ObjectARX programming interfaces to the AutoCAD LT product range.
AutoCAD Exposed - Information about undocumented features of AutoCAD, such as commands, system variables, and functions of the ADS, ARX, and AutoLISP programming interfaces.
