Let's suppose you want to lose weight. In such a case find a list of books that are written on that topic. Unless a book targets an important problem you are facing, it won't appeal to you, and your mind won't motivate you to read it.
Best sellers are not always great books, but your chances of finding a good book among them are much higher. Check the best sellers lists and see if there are any books that target problems or needs that are important to you.
Sometimes the best way to find whether a book is for you or not is to read the first few pages. Borrow some books from your friends and see if any of them appeals to you.
Amazon offers a feature that allows you to read a few pages of a book online before you buy it. If the first few pages appeal to you then there is a great possibility that you will like the book.
You have to keep experimenting with books until you find an author that you like. Once you do, you can buy all his books without risking anything. Usually if you like the writing of a certain author then you will also find his other books interesting.
Once you find few good books you will easily find new books recommended within their lines. For example, while reading the book 'The Everything Store' which tells the story of Amazon's success, you will find a direct recommendation for the book 'The Innovator's Dilemma'.
Do you like games? Then why not buy a book about games. When you buy a book you are passionate about you will feel like you want to read it and your chances of finishing it will be higher.
Avid readers will quickly tell you which books are worth your time and which ones are not. Don't make the mistake of buying any book they recommend if it doesn't match your interests. Remember you will only be able to read what you personally find interesting.
Most bloggers recommend certain books and they are usually really good books, but beware not to fall into the trap of believing a blogger who recommends a book just because he wants to get commission. Good bloggers only recommend the books they have read.
Do you like Steve Jobs? Then Google the books he read. Once you find such a list you can safely assume that you will like most of them.
Do you think Warren Buffet is a legendary investor? Then read the books written about him. What's even better is reading books written by the person you admire in the case that he writes.
When you buy a few books from Amazon, the algorithm will start to recommend books to you that you might like. They usually get it right and recommend very useful books.
Goodreads.com is a site designed to help people find the right books to read. It's a platform for recommending and discovering great books (see How to read a book really fast).