I'd like to share with you a private group on Facebook. It's called Free Reference Photos for Artists. It's a site where photographers freely share their photographs for artists to use as reference. You won't believe the quality and variety of images there! Many are of floral and bird scenes, but I also see cityscapes and countrysides. If I search for horses, the photographs I find are spectacular! You'll have to apply to become a member, but I think it's totally worthwhile.
I also find Wikimedia Commons to be very inspiring. Wikimedia Commons has a system whereby photographers can share their copyrighted photos without cost or requirement to contact the photographer. It's important to read the licensing agreement if you intend to actually copy a photo or use it in a way that can directly be traced back to that photo. But if you view a large series of photos for inspiration and create something different from any specific photo, you're fine. Here's the link: https://commons.wikimedia.org/wiki/Category:Images
At first Wikimedia Commons seems intimidating, but I do a search in the right upper corner of the page. When I hit the magnifying glass, the images I want pop up.
The floral designs you see at the top of this blog post were inspired by the numerous photos of anemones by various photographers on Wikimedia Commons.