I've thought about this quite a lot, and after trying to break down rapport in an autistic fashion, I've concluded that there's really no single book you can read to be interesting to most other people. What kind of topic is going to be interesting to most other people? What kind of behavior or skill is going to be influential or relevant to most other people? What kind of humor is going to be funny to most other people? There's no such thing, and approaching "being interesting" as "stamp collecting of interesting subjects" is going to doom you to failure unless you are targeting a specific group of people with specific mannerisms. And even at this rate, without the basics of rapport down, then any attempt to do this kind of targeted approach is doomed to failure.
What is the best general approach then to have interesting things to say? "Being yourself", except instead of being a cryptic faggot about it, we'll come up with a working definition: being at ease with yourself and others enough so that you can bond over common experiences, feelings, and interests. What is going to help you? Asking the right questions to get other people to open up and share information, practicing charismatic and relaxed body language, being observant, spontaneous, and vulnerable to encourage wit based off of what you both know, maintaining social awareness and following up after encounters, etc. Once you establish a connection with another person, then the topics will flow naturally, and eventually you'll discover whether you share enough in common with somebody else to be interesting, or simply have too many differences (and that's okay too).
Now, in the interests of keeping it Veeky Forums, what kind of books are going to best help you to accomplish these goals? A book on social skills, a book on psychology, a book on body language, a book on good conversation, a book on improv comedy (or something equivalent that improves spontaneity and wit), maybe even searching around the internet for a list of good questions to get to know somebody else or break the ice, and then PRACTICE PRACTICE PRACTICE. Once you have the basics down, then it's just intuition that you need to develop through trial and error, and then eventually you'll be interesting.
If somebody actually wants to be productive about this, like expanding upon the various categories or critiquing my approach right now towards a positive direction instead of burying this thread with another meme thread or criticizing the idea of both reading books and practicing with people to develop social skills, then I'll throw out a list of books that could get somebody started.