While reading books on Buddhism by knowledgeable, accomplished masters is valuable, there is nothing like reading Buddhist sutras themselves. For study, it is particularly useful to read the Nikayas. Reading the Nikayas is like having Shakaymuni Buddha sitting right in front of you teaching you directly. But, as a form of meditative practice, reading the Mahayana sutras is quite wonderful. Lately, I've been reading the Huayen Jing, the Flower Adornment Sutra, before I meditate. It is especially useful to read it aloud. Doing so has a great calming effect on the mind and expands the heart. Reading or reciting the sutras can bring about realizations that could not have happened so easily or quickly any other way.
This is akin to the old Christian practice of Lectio Divina in which one would read the scriptures as a form of meditation, reading from the heart, resting on the words as they are read, sinking in. Unfortunately, this practice has fallen away in Christianity, like so many of its traditions that could lead modern followers to deeper levels of insight.
Fortunately, Buddhism still sustains the tradition of recitation of sutras, though this practice hasn't taken root in the West like it has in older Buddhist cultures. Reading aloud the Buddhist sutras is so vital to ones development and is such a great complement to sitting and walking meditation, it's a shame that is it overlooked and neglected in the West.
Try an experiment. Buy the Flower Adornment Sutra Volume One by Thomas Cleary (you might be able to find a used one on Amazon - new ones are expensive) and read it out loud for about 15 minutes before you meditate and see what affect it has on your meditation. When you read it, read as practice. If your mind wonders, gently pull it back to focus on what you are reading. It's not important to read for understanding, but more for natural visualization. Just read with focused clarity but don't engage the intellect. Let yourself rest in the flow of the words in a relaxed but alert way. This can be a very mind and heart expanding experience, especially with the Flower Adornment Sutra. My Shifu , Venerable Master Sheng Yen, recommended this sutra to me 25 years ago and I am only just beginning to see why. I wish I would have made it part of my daily practice so many years ago! It is really quite wonderful.