http://tropicalbonsainursery.net/tropical_fruit_tree.html
Cheapest around for air layered longan. Have not ordered from them. If you do, let me know how it goes.
I have, most of his plants are rather small, but many are from cuttings, grafted or air layers, so maturity time is reduce as he states on his site. When I say cuttings, they were not air layers, that got cut off, after roots have been formed. He actually rooted the cuttings, after being cut off. Air layer is practically the same as cuttings, just that air layer plants, are rooted while still on the mother tree and cuttings are rooted after have been cut off, from the mature tree. The one, I got is advertise as a #5 plant, but looks smaller, like maybe a 1-2 gallon plant, instead. It didn't come with that large of a root mass/ball. But, it came fine and is slowly growing and surviving fine, so I can't complain much. Though, mine was more expensive($50+shipping), then that price in the link, since it was grafted and not an air layer. Wish, I could have gotten mine for the price in the link. Only have gotten it last year, around this time too.
So far, since I started this hobby of mine(quite expensive, I must say), I have gotten a few plants, from him last year, when, I first started collecting and growing tropical plants/trees. Have gotten 2 guava varieties(Emperor & Hybrid Pearl), Grafted Kohola longan, king Kong wax Apple/jambu, Lucoma and a mango seedling. Out of those plants, I got from him, that, I say is worth the price are the two guavas and wax apple variety, he has. You can't find other nurseries carrying those varieties else where, or at least, I haven't found them at any other nurseries yet. The guavas grew fast and would have been bigger 'n' taller, if I didn't cut them back to be more of a bush form, than tree. Speaking of guavas, on his Amazon store, many of his same plants are cheaper there than on his site. Like his #5 Pearl and Emperor guavas, are way cheaper there, than his site.
http://www.amazon.com/s/ref=bl_sr_lawn-garden?ie=UTF8&field-brandtextbin=Tropical+Bonsai+Nursery&node=2972638011-most of his plants are from cuttings, air layers, or grafted(reduce fruiting/flower time)
-they are small, for their advertise size with small root ball, but will survive fine, if taken good care of the plants and it's needs
-a bit pricy for small plants, but that's CA for ya