Picking the right native plant for the right place in your garden requires you to not only know your garden but which plants are native. I get considerable assistance from the folks at Evergreen. Their Native Plant database gives me lists of shrubs, trees, grasses and wildflowers that are native to New Brunswick.
The database has a search engine that helps you select the plant(s) that you are looking for, unfortunately not all the selections have pictures but the descriptions are helpful and so are the latin names.
The big problem that I still have is finding a local source for seedlings or seeds.