There is a new place for anyone who needs to find information about customizing Autodesk products. This new level of free support is called ADN Open and will be a great resource for people who can get by without the benefits of a full ADN membership.
You may have already experienced part of ADN Open by visiting one of the DevBlogs, such as this DevBlog that focuses on customizing manufacturing products. Part of the work my team has been doing lately is migrating DevNotes to the DevBlogs. These DevNotes make up a knowledge base of API examples that used to only be available to ADN members. Also all new technical articles that we create will be posted on the DevBlog.
The post by Stephen Preston has more details about ADN Open.