To get started with NetSim network Simulator, you can go through the following resources:

1. NetSim User Manual which will be available in systems where NetSim is installed  (<NetSim_Install_Directory>/Docs/HelpFile).

2. NetSim Experiment Manual  (<NetSim_Install_Directory>/Docs/HelpFile

3. NetSim Knowledge Base (https://tetcos.freshdesk.com/solution/categories) - Consists of a number of technical articles on various network technologies and associated FAQs.

4. NetSim File Exchange (https://www.tetcos.com/file-exchange.html) - consists of sample R & D projects related to different network technologies along with source code and documentation.

5. TETCOS Youtube page (https://www.youtube.com/user/Tetcos/videos) - contains a lot of videos on NetSim features, projects, monthly webinar recordings, interfacing with other tools etc.

6. Support Portal (https://tetcos.freshdesk.com/support/tickets) - Users can raise support tickets if they face any difficulty with using the software.