Would it be possible for someone else to create the account for you, or would it be inextricably associated with that person's hardware? I guess it's probably limited to one account per device to control the licensing, which would be a non-starter.

iCloud accounts aren't hardware specific. They're linked to an email address.

Go to an Apple Store then. Set up an account on one of their lovely machines, and then skip back home and finish it on your Windows machine.