The Folder Export/Import user interface consists of a standalone application that is installed with either the Admin Tool or the GUI Client. The same interface is used for both the exporting and importing data.
How you invoke the Folder Export/Import tool depends on how it was installed.
If you installed it with the Admin Tool (or Vault Server) installer, a shortcut will exist at Start Menu->All Programs->SourceGear Vault->Vault Folder Export Import.
If you installed the Vault Client, it will exist in the Vault Client installation folder (usually c:\Program Files\Vault Client) as VaultFolderExportImport.exe.