The first keyword in your search should be the name of your state or of a geographical area in your state, such as a national park or other well known feature.
Use Google to discover geographical ares and environmental issues for your state. For example, you could look for lists of threatened or endangered species.
These keywords will help you get started. Be persistant; you may need to type many searchs before you find a book with a useful chapter. See the suggestions on typing keywords in the box to the right.
Once you discover anything about the environment or ecology of your state, use that information in your next search. For example, the name of a natural feature of your state: Channel Islands, Big Sur, Badlands, vernal pools, glaciers, etc. Or the name of an animal or plant in the state: golden eagle, kit fox, sea otter, etc.