That link goes to a page that says "If you have an *account, billing, or purchase question,* send our iTunes Store support team an email using this form. If you have a technical question about iTunes, contact Apple Technical Support."
The link to "Apple Technical Support" goes to a page that says:
Telephone support is available for customers using iTunes with any of these Apple hardware products:
* Mac
* iPod
* iPhone
* Apple TV
Given that my issue is in the "Using iTunes Store with Windows" forum, none of those Apple hardware products is involved.
The other option on that support page is the "Apple Expert for iTunes" call-back service ... but even if you ignore the requirement for a serial number (I do have an iPod), that service doesn't include support for the iTunes Store.