Huon pine is primarily native to Tasmania and rimu is primarily native to New Zealand but also grows in Australia, New Caledonia, Malaysia and Borneo. The folks down there probably don't get them confused at all, I just thought I'd point out some possible confusion in the USA.
Part of the confusion probably stems from the fact that huon pine, Lagarostrobos franklinii, used to be designated as Dacrydium franklinii, whereas rimu is the common name for a couple of closely related species, Dacrydium cupressinum and Dacrydium nidulum. Also, the rimu species have huon pine as one of their common names, although they probably really shouldn't. I am not familiar with the two woods up close and personal, but it appears that they should be fairly easy to distinguish from each other.
The name-sets, as best as I can distinguish them, are as follows (the family is Podocarpaceae):