A very nice lady, I think her name was Maria or something that started with a 'M' , was really helpful so I was wondering where I could write some positive feedback.
Welcome to the PlayStation Community.
Frist of all it's god to hear some good news about Sony's customer support, it's usually only bad stories we hear here!
I agree with the above, I would use the email address that you may have already used when contacing them for the issue you had, or wait for a possible feedback email from them.
Customer Service - 1-800-345-SONY (7669)
Account & billing Support -1-877-971-SONY (7669)
Available Mon to Fri 8am - 8pm PST