any good websites or tips on saving cash?

I only make about $10 an hour and have a young child. Rent is taken care of in my home but all other household bills including cable, computer access, phone, electricity, mine and my childs health insurance (a whopping $100 a week) clothing for myself and my child, and food for the whole family falls on my shoulders. I need to start saving money and I'm at a loss as to how I can do this with all my other responsabilities.