I have belief, I just don't have religion.
Nothing is not about making the case against religion from a scientific or logical standpoint -- if you are looking for that type of argument, you would do better reading Richard Dawkins. Instead, Nothing is an extremely personal memoir of being an everyday garden-variety nonbeliever in contemporary America -- we read about Lalli's early encounters with institutionalized religion, her struggles to define her nonbelief, and her efforts to defend herself from her rabidly Christian in-laws.
Nothing is a fast and easy read with a nice combination of humorous and cringe-worthy moments, but it's not very deep -- I ended up watching a whole slew of CFI Ontario YouTube videos to get a better grasp of Lalli's beliefs.
Nothing: Something to Believe In by Nica Lalli (Prometheus Books, 2007)