It's already been said, but it bears repeating -- check your local library. Even if you're in a rural spot, your library may have hooked up with a larger urban one.
My library lets me check out 15 ebooks at a time, and I can keep them for up to 3 weeks. They have a LOT of titles, enough that I can always find something I'm interested in reading within a few seconds of browsing. I haven't been back to the physical library since I downloaded their app. :)
And if I don't like it once I start reading, it's one click to return and remove. It definitely makes me more willing to take a chance on reading things I normally wouldn't.