These are all resources and reading materials that I found indispensable before, during and after trips (all can easily be brought to a Parisian cafe to enjoy with espresso too!):
My favorite, favorite, favorite online tool to find the best and cheapest flights for ALL my travels is Skyscanner. If you haven’t used it before, seriously go check it out! I use it for my trans-atlantic bookings as well as all my bookings while in Europe or intra-country travel. Seriously the best!