Chapters sponsor programs related to growing native species. Many have plant sales and plant raffles. All have knowledgeable, interested people.
Decide what you want to create. Native plant gardens range from extreme formality to casual wildness.
Check the soil survey, dig a hole. If you have a natural soil, you will likely find that the plants that originally thrived in an ecosystem associated with that soil, as listed in the survey, will do well for you. If you live in a subdivision, you may live on fill. Check the pH, check the soil texture, and consider that your site is probably different from what it once was. Remnant trees or large trees in your area can give you a clue to the type of habitat that existed prior to the subdivision. Plan for the current site conditions that exist. Read the books listed on the www.FNPS.org website.
Many Water Management District offices, parks and extension offices have these.
Check out native plant nurseries in your area. Check out local retailers. Some of the most easily grown natives are very widely available.
Tom Heitzman at Sweet Bay Nursery!
Plants adapted to the climate of your region will do better than imports. A mahogany (from the Florida Keys) is not native to Tallahassee and will likely freeze during the first winter.
Almost all newly transplanted plants need extra water. Check out and use xeriscape principles to get the "right plant in the right place."