It could be friends or family who you know know shop online a lot. You could transfer all the money you'll spend to one Paypal account to make the check out process less complicated. This would allow you to take advantage of free shipping [wherever they are offered] and at times get some discounts on bulk purchases. Haven't tried this? Find friends who regularly buy their "stuff" online and tell them of the savings you'd make if you shop together.
I often shop at stores where it is cheaper if you buy in bulk, and I always make the most of these offers with my friends. I will never need to buy food in such huge amounts as they offer, but I always find that if we club together it can be a lot cheaper than it would be if we were in the shops, and therefore it is a great thing to do. Making the most of free shipping is important too, as it can save you a lot over the course of the year. It is amazing just how much money you can waste on shipping without noticing it, so you should definitely try to save it whenever you can.