Just to allay your fears:
The scam is to get you to part with your cash ( which thankfully you didn't ).
It is unlikely that they have put anything on your system - other than the software to give them remote access.
I assume that you have remeoved the installed software?
To confirm this I will PM one of our security experts and ask him to take a look at your system for you - just to be sure.
To be on the safe side I would advise that you change any passwords to banks etc.
I would also inform the banks / credit cards what had happened - they will have more advice.
If you don't keep delicate information on your system then you should be perfectly OK.
However, again just to be certain, DO NOT use that particular machine to access bank details etc. until you get the all clear from Starbuck or etravares