I ordered another DNA test. It was on sale (hee hee). 23andme has discounted their genetic testing from $500 to $100, so I ordered a kit. You also need to subscribe to their update service for one year at $60, but the total is still much cheaper than $500.
If I understand this test correctly, I will possibly find any relation- not just direct maternal lines.
I was alerted to this sale by a post of a distant cousin. I located her through my aunt's mt-DNA test. We have a common female ancestor- just no clue who this woman was.