To prevent frozen water pipes here's a few things you can do.
Add heat tape to the pipes.
You can go to lowes home depot or any other hardware store and purchase some electrical heat tape. You wrap this heat tape around the water pipe and plug it into an outlet.
When it gets cold enough the heat tape will turn on by itself and will keep the water pipes above freezing temperatures.
Use pipe Insulation.
Go buy some pipe insulation and install this pipe insulation onto your pipes. This will keep them from freezing also.
Let the water drip.
On really cold days you should turn your faucets on to a slow steady stream. Although water can still freeze when running it helps prevent the water from freezing when the water moving.
It might raise your water bill up a bit but the water bill will be much cheaper than a plumbers bill or the inconvenience of having frozen and burst water pipes.
Open cabinets.
You should open any cabinets that have water pipes inside them such as under sink cabinets.
This will allow heat to get to the pipes and also prevent them from freezing.