While I don't have any experience with any plants that contain those names, here is a web site that you can search:
The Royal Horticultural Society Plant Finder
Type in the name, search and browse through the results. I see that there are results for each of the names you requested, although some of the plants appear difficult to find.
The RHS Plant Finder is a resource that accomplishes several tasks: not only does it record which nurseries supply which plants (all UK unfortunately), but the Royal Horticultural Society also devotes staff to ensuring that the names are accurate. It is the primary resource we use at UBC for names of cultivated plants.