Dear Ms Hewitt:
I wanted to thank you for a wonderful concert on Saturday afternoon here in Stratford. I missed your prior appearance here (way back almost 30 years ago) so was determined to see you this time and was not disappointed. It's great that you still take the time to travel to smaller, out-of-the way venues to allow some people, who would otherwise not be able to hear you in person, to do so. Don't leave it so long before you return - and next time get Mr Miller to come up with a Fazioli for your performance (lol). Regards:
Joe.