Could not load file or assembly 'Microsoft.Office.Interop.Excel'

[dethredic]

Remove the COM reference and add the same reference but this time in the NET references, then compile your application, and then you should see a new dll file in the debug/release folder.

Installer it's a Setup Project (MSI File)
XCopy, just copy the files directly without any kind of setup.

BTW, what VS version are you using?
In 2008 version you can found the references here, default installation directory C:\Program Files\Microsoft Visual Studio 9.0\Visual Studio Tools for Office\PIA\Office11

When I go projects-> add reference there is no "Microsoft Excel 11.0 Object Library" under the ".NET" tab.