To the OP, as they said some on here are not all that appreciative of what you might be considering. I on the other hand have never lived on their side of the tracks. I would suggest you do some googling and reading (I believe in reading and learning. The whole teaching to fish vs giving a fish thing). Do some googling on man in the middle attacks, arp poisoning or spoofing, cain and abel, airpcap, wireshark... these will lead to other areas of study. I believe you can even find some youtube videos of this sort of thing.

Sorry to anyone offended.