You can attach to a running Windows service the same way you attach to a general Windows process: VTune Amplifier XE->Project Properties->Attach to process->Process Name or PID.
You can obtain the process name for a service in the Windows (Win7) Control Panel->Administrative Tools->Component Services->Services(Local)
Thank you for the screenshots. Now I see that the process was started by the System user. This is not something we support with attachment, sorry. We will consider how to fix that in the future releases.
Im not an expert in Windows services, so you probably could find a way how to launch the service process as not System user this should help to workaround the problem.
Thanks again for the reproducer.