Hi,
I grew up in Salisbury and only left the area 2 years ago. Not a dressage rider but I have plenty of connections down there I could check with if you needed. Please be aware that while Salisbury and Ocean City are THE big cities in the area they are over an hour’s drive from you and there’s not a lot of speeding to be done - the cops will nail you in most areas and the locals drive like they have nowhere to be. (I’m a local - I can complain.
As someone newly moving to the area you may never complain about the locals. Them’s the rules!)
I personally would never live in Ocean City. During the winter it’s great. During the summer it’s a mad house - tourists (stupid tourists), mad traffic and accidents are a guarantee. Expect your route home from about April to October to increase by 15 to 60 minutes on Mondays, Thursdays and Fridays. Tuesdays and Wednesdays are only good in comparison and you might as well plan to stay home on weekends or be out all day.
Salisbury isn’t bad - it benefits hugely from the new blood of the university. Fruitland and Eden just south of it are actually accessible and pleasant places. In Salisbury the better apartments tend to be up north, which means Salisbury traffic - still better than Ocean City. There’s also Pocomoke which is closer to you but not nearly as big city although at least it has chains more impressive than Royal Farm. (You will become a Royal Farm convert - mostly because there’s nothing else. Also, I hear their chicken is great.)
As far as farms/dressage trainers go: there’s Deri Jeffers down in Onancock (that’ll be south of you by a fair distance and I’m not sure that she boards), Renaissance Stables in Salisbury (boards and there’s a trainer), there’s a lesson barn outside of Chincoteague run by an event rider - they do boarding and I believe she has a dressage ring set up, someone mentioned Castle Farm in Snow Hill - they have a nice indoor and host clinics. With Snow Hill you run into an issue similar to OC - route 113 can be a bear but you’re mostly living off of it in Snow Hill. Also I enjoy Richard Williams down in VA. I had one dressage clinic with him (the only time I’ve ever ridden in a dressage lesson/clinic) on a friend’s horse who promptly bolted, launched himself into the air and attempted to kill me. After complimenting me for staying on he gave me a very nice, kind lesson.
Overall PVDA is thankfully pretty active because the area’s ultimately not all that focused-horse-person friendly. They do shows and bring in clinicians several times a year.
If you have a particular question I’m glad to answer and I can call on some actual dressage riding friends in the area for advise in at least the Salisbury area. (What really annoys me is there is another dressage trainer in the area that friends rode with and I’m blanking. I can check on that if you’d like.)