I order and buy from lots of places, but my mainstay for mail order is Willis Orchard Company in GA, USA. So far, they’ve sent me everything on the packing slip (no missing items), sent only healthy plants (not dead sticks), and every live plant I’ve planted from them survived planting (my only losses have been deer-related, in 1 case directly from my heeling-in trench!). That’s a 100% success rate—no other mail order nursery has come close. They have really good prices, which is great. My only issue is their selection is a little narrow for what I do (they have lots of Rosaceae, which doesn’t always like rock-hard moist clay), though they do still have a wide variety of highly-regarded cultivars and extremely cheap straight species.
From Willis, I’ll probably get a bunch of wild American hazel (Corylus americana; need to ask about parentage) and wild American persimmon (Diospyros virginiana; they’re descended from Yates, which is an early 90 chromosome type, being smaller, disease-resistant, and self-fertile) on the cheap. For named cultivars, I need to replace blackberries and raspberries that were destroyed by deer (I’m going for the thorniest, nastiest ones I can get—they will be edible hedges) and round out more of my fig collection (I’m trying to hit all the major flavor profiles while also choosing the most humid acid clay-loving and disease-resistant cultivars of each flavor). May even try some banana—I think it’s warm enough that they’ll survive (blazing zone 7/8) but I have no idea if they’ll fruit (and I’m personally opposed to container gardening except for occasional, special purposes: my plants need to work for me, not the other way around, as much as possible!).
I also plan to try One Green World for the first time, after more disappointment from one of the other big PNW nurseries (missing plants, only 50% of the previous winter order left alive as of today, etc). I’m getting at least a maypop (Passiflora incarnata), feijoa (Feijoa sellowiana), and some strawberries (Fragaria × ananassa), maybe more when I see what the price tag comes out to. Then I want to start filling in some other non-fruit perennials, including oilseed camellia (Camellia oleifera; no tea for me, please!), mountain pepper (Tasmannia lanceolata), and rhubarb (Rheum × hybridum).
Other than that, I’m getting everything from pollinator plants to conifers (such as pseudolarch) from seed from various sources, maybe a special live yucca. I have a very specific list of species and cultivars, so there aren’t a lot of options (at any price) for about half of my needs. No time to waste on species and cultivars that don’t work well here—once I get solid genes that prove themselves, then it’s time to propagate.