S. purpurea should be easy to spot because of the flowers this time of year. Sundews usually betray themselves with patches of red.
However it is usual for inexperienced carnivorous plant hunters to trample unknowingly on the very plants they are looking for and not spot anything until they get home and find a crushed plant stuck to the bottom of their shoes.
Do not under any circumstances introduce any species indigenous or not. You would be changing the natural accession of the biome as well as disturbing the gene pool. The last issue of Carnivorous Plant Newsletter tells of how some one introduced a Sarracenia leucophylla into the middle of a private preserve of one of the few remaining stands of pure S. alata. The plant went unnoticed for several years and now the population is no longer pure.