Been There Farm
I haven't been there (lol, unintentional pun) in person yet, but it's near my house and I figured I would check it out sometime. It looks nice. I was looking up lesson/boarding facilities near my house (for after I graduate uni, no horse yet, haha) and that's the least expensive one that I've been able to find through an online search in my central NJ area. $300 per month for field board. Of course, someone else may be able to advise you better, but since I had it in mind I figured I'd mention it. :P