I want to study philosophy in my own time, any books to recommend?

All of them, but for a delightful beginning I would start with the dialogs of Plato. They are very readable and it is a fun way to learn about basic questions. Then I would grab an introduction to the Enlightenment philosophers, which one you choose is not that important. After feeling like you don't understand anything for a while, which should happen if you are learning, try to get your hands on anything by Brand Blanshard. Most of his works are out of print, but I have seen used copies of Reason and Belief for sale at Amazon. Blanshard is recommended for making the main problems of philosophy accessible.