Call me insane, but I start shopping for Christmas in May/June when a lot of the stores have their semi-annual clearance sales.
I make a list of people I need to buy for, how much I want to spend, and then write down every gift I purchase and how much I paid for the gift. I put all of the items in a plastic box in the basement. This really helps because it's a little bit at a time and I'm on a strict budget. This also allows me to buy "extra" gifts if I'd make new friends, because I have all of the major people in my life already done by the end of September.