Personally, I can't tell people that I'm an Atheist -except you guys on TA- so no one has asked me this before, but I always watch and read debates and discussions between Atheists and theists. And I see that this question "What if you die, then you find out that there is a god? What would you tell him?" is always asked.
In Islam specially -and I think other Abrahamic religions- they say that people have free will but they contradict that by saying god writes everything each and every one in the world does! So when an accident happen, muslims tell themselves "it's written and we accept whatever allah has written for us". And when I say everything, it's really everything! even sneezing! lol
So if I die and find allah and he wants to send me to hell, I would tell him "why do you punish me? You 'wrote' for me to not believe in you, so can you please tell me the nearest path to heaven? And you are the one who should go to hell for killing so many people"