Cary Fowler thinks many heritage (or is it heirloom) apples are alive and kicking:
While some of these varieties are gone, many still exist. In fact, I have most of those pictured in my own orchard. Old varieties can be obtained from a number of sources such as Cummins Nursery, and Century Farm Nursery. Recently a new organization — the Temperate Orchard Conservancy — was formed in Oregon to rescue Nick Botner’s 4000+ apple variety collection. Even allowing for synonyms, this might be the largest varietal collection in the world.
Do your part and plant some!