How do we speak to a human about charges that are invalid?

Hi ...

First follow the instructions here > How to report an issue with Your iTunes Store purchase

And you can use the email form here > Apple - Support - iTunes Store - Contact Us

More contact information here > http://www.apple.com/support/contact/

Answering your specific question, there is no telephone nor live chat support for the iTunes Store. The web form Carolyn refers to is the only way to contact them. If you have invalid charges on your credit card, your first call should be to your bank to report the charges.

Regards.