Are you aware of the Gutenberg Project? [link] They've got quite a collection of free ebooks. I'd recommend Edgar Rice Burroughs's Barsoom series, starting with Princess of Mars, the book that was the inspiration for the recent Disney movie adaptation.
As for something new, and "Indie," I would recommend The Sable City, by M. Edward McNally [link] It's the first of the "Norothian Cycle," and I can say from experience that it is very much like a Dungeons & Dragons campaign. I'm currently about 3/4 of the way through, and I'm still enjoying it. The worldbuilding, while not terribly original, is highly intricate and well-realized. The plot is complex, has several interesting and well-developed characters, and focuses on multiple independent threads, all of which end up converging on the titular Sable City (and what it is is only revealed about half-way through, so I won't spoil it).