Well, it comes down to finding the best used book store. In America we have so many used books available across the country. The most popular location for those is in the town library, they sell used books usually in a section in every library or once or twice a year. You can find them on https://booksalefinder.com/.
There are also little libraries popping up all over the country where neighbor's put books they are done with. You can find them all over America at https://littlelocator.org/ .
The trick is finding the genre you like after you find a steady source of assorted literature.
Some people like to strictly focus on non-fiction such as Biographies, and Science books. Other's can only handle fiction. What got me into reading was Hardy Boys when I was a kid. It is important to build reading habits when young as it is a great way to absorb information rapidly.
You can then take your genre and start exploring the top authors of the current age and of previous eras. My favorite site for locating my next read is checking reviews of GoodReads.com. Here is an assortment of my book's read, you can check out my profile for a good overview of American Fiction:
So to recap,
- Locate used book source (even amazon.com sometimes)
- Pick a genre
- Select a few author's you'd like to explore
- Use resources like GoodReads.com to connect with other readers.
- Tag your book