Search notes:

%APPDATA%\Microsoft\Windows\Start Menu

This directory contains a user's (non-shared) entries in his Start menu.
The entries that are shared among all users are found in %programdata%\Microsoft\Windows\Start Menu.

Determining the path with PowerShell

The PowerShell prints the location of this directory with 
[environment]::getFolderPath('StartMenu')

See also

The subdirectory Programs
The .NET enumeration System.Environment+SpecialFolder

Index