@speakingtohe: I can't help but worry about it. How it behaves is wrong, and that offends me. That doesn't mean I will be able to fix it, but that is another issue.
@theducks: regular expressions like this one work. I need to play a bit to ensure that I am not doing something wrong.
Code:
series:"~^(A|The|An)\s+[T]" or (series:"~^[T]" and not series:"~^(A|The|An)")
Of course, you change the letter in the [ ] to be the "first letter" you click.