Pinelands Nursery and Supply as part of the Native Plant Society of New Jersey. They're a wholesale nursery who's doors are closed to the public except for the occasional gardening club and horticulture related events.
While on the tour though I was thrilled to learn that the owner's son is starting up a branch for smaller orders meant for the general public. It's called Pinelands Direct and I can happily say I'll be ordering from them in the future. Their website could use a little work and they don't have as big a selection as the main Pinelands Nursery, but they are selling some hard to find plants such as Seaside Goldenrod, along with more typical native plant nursery plants.
Regardless of which nursery you're buying from, though, you'll be getting plants grown from local seed stock native to New Jersey, PA, NY, DE, and generally a 250 mile radios around their nursery. Some native plant gardeners and conservationists find that important. Personally I don't, I'm not that picky but it is nice growing something that tends to be better adapted for the local area.
Speaking from experience, I buy from a lot of online nurseries and sometimes when I order from a nursery based in Florida the plants don't always survive the winters. So growing from local genotypes has its benefits. When you do find success though it's sometimes fun to mix and match genotypes to extend the bloom or encourage fall color at different times of year. The Black Eyed Susans grown at the Mt. Cuba Center in DE bloom right alongside Symphyotrichum laeve 'Bluebird' (click more photos), whereas back at my house in NJ, they've finished flowering long before most asters have even flowered. However I do happen to have two genotypes of New England Aster. The local one found here in NJ blooms a solid month after the one I ordered from a Massachusetts nursery. Their bloom is so far off that one is setting seed while the other is flowering.
After the tour, there was a native plant sale. We didn't get full reign over the place like we did at the New Moon Nursery but I got my Seaside Goldenrod (and 8 other plants) so I was happy. The quality can't be beat for the price we paid. The plants are in a 4 inch square pot (I believe it's a quart) and they all had thick solid stems, they were very huge and overall healthy for the price paid. Some of the plants I got were a little root bound but frankly I get that from every nursery that sells anything larger than a plug size, and it's a simply fix too, just cut off the offending roots and loosen up the sides so I don't fault them for that. I'm very happy with the plants I got! (And added a link to their site on the side bar.)
He talked a little about why he's not more open to selling to the public. The benefit of wholesale is how automated he can be. They collect seeds by the millions and germinate them all at once. He gets huge orders of plants. The minimum order is $1,000, and it's not uncommon for people or order plants 1,000,000 at a time. Taking the phone call for that order takes up about the same amount of time as it does for someone only ordering just 10 so it's REALLY not worth his time.
It was great seeing his son stepping up to the plate and running the retail side of things though. I wish his selection was as good as his the wholesale... actually I'm not sure why it isn't, (maybe those are the only plants they keep in stock year round?) whatever the case, I think they're the only nursery that really sells Seaside Goldenrod over the internet.