If none of these materials is available to you you can always elect emergency service to soak rags or towels in hot water and wrap them around the frozen pipe. This will probably take longer than any of the methods previously mentioned.
When you get to the house stand if front of the toilet and locate the water shut off valve. Should be down below the toilet on the wall. Just turn it off (righty-tighty) completely and flush the toilet. All the water should have left the tank, well at least most of it. If there is remaining water line repair get it out with paper towels or a rag. The important thing is that no more water came in. If it did then your valve is not shut all the way or not working and you need additional help.
If you bought the same unit it should line right up, if you were unable, you will need to remove or add length to the existing piping. This may require you to splice together copper with plastic, don't let this scare you the hardware store will have all of the necessary parts.
Once you have disconnected the tank remove it from your work space. Do a thorough measurement of the remaining pipe for reference when you go to the hardware store. I will be honest with you, you might need to make a few trips back to the store. Once you get the new tank, slide it into place to line up the plumbing.
When the drain line stops up it is just a matter of calling an air conditioning contractor to come out and clear the drain line. While he is there he will add an algae preventative to the system to prevent future occurrences. Proper air conditioner maintenance is the key to preventing water line repair leaks.
Turn the water off at the main shutoff valve at the street. You should be able to take a pair of pliers(or your bare hands) and turn the valve at the water meter to shut off the water to your home. Once you have shut off the water you can cut the pipe around the leak and make the repair.
Water leak detectors can keep your home safe. They can give you the peace of mind knowing that you won't come home to a house full of water. It is a lot less expensive to buy a water detector than it is to pay thousands of dollars in home repair costs.