I saw a magazine at Walmart today that has it laid out step by step. I forget the name but it is this months issue.
its called the pc builders bible by pc gamer.
also, look inside your current pc and used that as reference.
i just build my first pc last week and it pretty easy. the only problem i had was the power for fans. the cable used for to connect the fans wasn't label clearly.
don't sweat it. take your time.