The best online forum for Vectorworks users is the Vectorworks Community Forum (aka the Techboard). It is a great place to post questions about using Vectorworks and to read about others' experience with the software. There is also a large section for sharing resources, including Textures, Symbols, Hatches, Templates, Marionette objects and more. As of December 2016, the Vectorworks Knowledgebase is also housed within the Community Forum.
If you do not already have a an account, make sure you register in advance of when you would like to post, because the manual approval process may take a a bit of time.