I suppose they aren't new to most of you, but I was just out in Portland, Oregon for a Perennial Plant Association meeting and on Wednesday night we had many nurseries selling plants. There were a NUMBER of fabulous nurseries there, and two had an INCREDIBLE assortment of alpine plants. And They Sell Mail Order!
Do check out Edelweiss Nursery in Canby: http://www.edelweissperennials.com/index.aspx
Also Wild Ginger Farm in Beavercreek, Oregon: www.WildGingerFarm.com
With the very sad closing of Seneca Perennials, it was a great comfort to find two top notch nurseries that offer a wide palette of choice plants.
And don't forget www.cistus.com: Sean Hogan does not have many high alpines, but he has everything else you can imagine.
Good news, eh? (I suppose you will tell me you've known these places all the while..)