These links are courtesy of Chris Nicholson, presented as part of his program on Dec 4th 2017.
www.PhotographingNationalParks.com (at this site you can sign up for his newsletter)
Other sites to check:
www.PhotographAmerica.com (newsletter by subscription)
www.chimani.com (GPS enabled maps for the smartphone)
www.photoephemeris.com (The Photographer's Ephemeris® (TPE) is a tool to help you plan outdoor photography in natural light, especially landscape and urban scenes. It is a map-centric sun and moon calculator: see how the light will fall on the land, day or night, for any location on earth.)
National Geographic National Park Guides, available at https://shop.nationalgeographic.com/
And also available on Amazon.