It seems that I do not have ArcGIS templates in VS 2010 templates folder -
\Program Files (x86)\Microsoft Visual Studio 10.0\Common7\IDE\ProjectTemplates\CSharp\
and as a result ArcGIS templates do not show up as installed templates for New Project.
To get these templates will I need to reinstall VS or can I get the zipped ArcGIS templates from somewhere?
When creating a new project using an ArcGIS template, you have to make sure you target the .NET Framework 3.5 instead of 4, which comes up by default 
Reinstalling the ArcObjects SDK will install the VS2010 templates provided VS2010 is installed. I had this happen as a result of installing the ArcObjects SDK before installing VS2010. I had been using VS2005, and after installing VS2010 the ArcObjects templates were not available. Reinstalling the ArcObjects SDK resolved the issue.
Please don't take this as condescending - I say it because I made the same mistake myself! Did you actually install the developer tools when you installed ArcGIS? I made the mistake of thinking I had when I really hadn't because I assumed it would have been installed with a complete ArcGIS install from the installation source I was given.
But in the case of the ArcGIS distribution that my university uses, the developer tools were not included with the .msi installation tool that was distributed on the school's software installation website. I had to the actual installation DVD in order to install it (my university provided it as an ISO).
Double check your installation source DVD, run ESRI.exe, and then make sure the sources you need from "ArcGIS Desktop Developer Resources" are fully installed.
