When you go to the bin directory at C:\Program Files\PTC\Creo 2.0\Parametric\bin:
1.) Right-click reconfigure.exe and run as administrator. This will open up the PTC Installation Assistant.
2.) Step through the process by click Next.
3.) In the Applications to Customize section, accept the default selections (including Enable Quality Agent) and then click Install.
This process should create the proper .psf file in your bin directory. If this doesn't work, please let me know.
It sounds like your installation in incomplete. This happens sometimes (depending on your connection speed) when using the web install. I would suggest you download the full DVD image and then reinstall using it.
My apologies, I didn't realize that ptcsetup had been renamed. Obviously the guys writing the warning message didn't know either .
Curtis' instructions should get you going.