This guide provides information on how to use the AutoCAD .NET API with Microsoft Visual Studio and the programming languages VB.NET and C#. Information specific to developing applications using Microsoft Visual Studio can be found under the topics “Getting Started with Microsoft Visual Studio” and “Develop Applications with Microsoft Visual Studio.”You can access the AutoCAD .NET Developer’s Guide online:
Programmers developing with the .NET Framework using a development environment other than Microsoft Visual Studio can skip these two chapters. However, all of the example code in this guide is presented in VB.NET and C#.
Getting Started with Microsoft Visual Studio
Basics of the AutoCAD .NET API
Control the AutoCAD Environment
Create and Edit AutoCAD Entities
Dimensions and Tolerances
Work in Three-Dimensional Space
Define Layouts and Plot
Develop Applications with VB.NET and C#
VBA/VB to VB.NET and C# Comparison
VBA to VB.NET and C# Comparison
AutoCAD .NET Developer's Guide
Here is also some great screencasts from Microsoft.