Mystery Horse's Past

This is a long shot, but I have a request for all horse lovers out there. I rescued a TB mare in April from a livery rental in southern Ohio. Call it fate, but we found eachother one cold morning. I found her tattoo two days after I got her home, and have since been on a quest.
From what I have researched, she went through a meat auction once where her previous owner purchased her. She had been badly injured at one time. My vet says she broke her pelvis, and quite possibly fractured her vertebrae. Imagine, carrying ill seated tourists on a bad back through state forest trails.
I have talked to the owner who had her in the beginning, and I know where I bought her, but I am working on a book and I am trying to find out the middle of her story. Here is what I do know. Her registered name is Larry's Lassie, she is from (and raced at) the Finger Lakes region of New York. She is 16, bay, and the sweetest mare in the world. She knows the name Midnight. My guess is she went through the auction in Sugarcreek Ohio. If anyone knows any small tidbit of her past, please contact me. Fate placed this mare in my hands, it is meant to be that I tell her story.
Thank you all. -M

Have you tried contacting the Jockey Club? I think most racehorses TB's use their registry. Good luck on your quest and bless your heart for taking in a lady in need.

Yes, the Jockey Club is how I traced her tattoo. When I spoke with her original owner, who raced her, he told me that she was given away free, as he always does, and could not remember to whom. Same with the trainer.
I'll probably never find out all the missing years, but it is a wonderful quest. I enjoy the challenge, and I do love this dark lady who has come into my family's hearts. Thanks!! -M