What are you looking for specifically?
Are you interested in the historical/philosophical perspectives? Are you after the sacred texts?
If you haven't found
this site, it's pretty cool. It's basically an organized source for public domain titles, and it allows you to download them in any format. And depending on the title, you can also find audiobooks.
For example, there are the following titles on Hinduism:
All the stuff on the website is older, but at least it's free and convenient in terms of finding compatible files to use on your reader.
I suppose this is a start.
So, what are you looking for? What do you know about Hinduism already?
If you haven't already done so, I highly recommend starting with the
Upanishads, a foundational sacred text of Hinduism. It's absolutely gorgeous. I'll also recommend the
Bhagavad-Gita, which is a section of the epic
Mahabharata. I haven't read the wider epic yet, but I want to one day. The
Gita is definitely worth reading if you haven't done so already.
The title listed as
Hindu Literature above contains the
Ramayana, which I've heard of but haven't taken a look at yet. It's another of the ancient epics.
I'm assuming the last few titles on the above list are more or less "about" Hinduism than "of" Hinduism. I'm not sure what it was you were looking for specifically, so here's a bit of a scatter shot.