I like how it took exactly one guess to figure out who you were talking about, that means the word is getting out so hopefully nobody else will have to go through this in the future. Jingles for a happy outcome. Fight like hell.
Sigh, all I had to read was the third paragraph about the "stallion owner" purchasing the mare and foal on payments to know who it was Why, why is this still happening? Honestly, it is like a car crash taking 3 years to finally come to a complete stop.
Well, if you are in need of a certified Equine Appraisal for your court case, I would be happy to offer my services pro bono. At this point, the entire equine community needs to start rallying together and getting this breeder STOPPED!
You should be going directly to the person whose property this horse is on, and mention that you will be suing them as well. Or, just go and pick said horse up I doubt an associate of this person will enjoy the fees and headache associated with this ordeal.
It's a small world, if this horse is listed for sale, you should be able to locate it. Whatever happens once the horse is located, well,
I would also make up flyers and send them around the every feed store, tack shop, Veterinarian, Farrier, boarding stable,etc. in that area. Someone knows where this yearling is being hidden. Put on the flyer that the person who has this yearling can be facing legal problems but if they contact you and return him you won't go after them. Your lawyer will know the wording to use.
Also contact the local newspaper - if they won't do an article consider taking out an advertisement.
Summit Sporthorses Ltd. Inc.
"Breeding Competition Partners & Lifelong Friends"
If this person is illegally listing your horse for sale on websites, why don't you contact those sites and have the ads removed? At least while you are looking for her you can make it more difficult for the filly to be sold.