I think he problem is he's 11, been racing 9 years - meaning he's been raced every year since he was 2 years old.
Your ad doesn't state how long he's been out of racing, so horse could be very bad for a not very good rider - wanting to run on trails, etc. If that's not true you need to add more information about what type of re-training he's had since he came off the track.
Also sound like horse has some (probably minor) ground handling issues. Sorry to say ad reads like you want an experienced rider to help you re-train the horse on the ground and on his back. I could see experienced horse people that currently lack a horse riding him for free and helping you re-train him, but in the current economy having to pay $200+ a month (the + is to cover vet bills but I assume you're paying farrier bills?) it's not worth the time and money for 99% of the experienced riders out there.
I hope this comment helps. I'd re-word the add with more details on how he acts on the trail, in the arena, if he jumps, what type of re-training he's had, etc. otherwise you probably won't get any responses - especially in the Tampa area which isn't far from Ocala where you can buy OTTBs for a dime a dozen.