1. Flip the wire arm down inside the freezer (it's to the right, or in front of, the icemaker).
2. Make sure water is getting to the back of the refrigerator.
3. Make sure the icemaker is plugged securely into the wall of the freezer.
4. Make sure the freezer temperature is below 10 degrees.
Are you pretty handy? Are you confident enough to remove some screws? You feelin' lucky, punk? Well, are ya? (Read the preceeding two questions in your best Clint Eastwood voice.) If so, continue on to #5, otherwise, go directly to #7.
5. If all the above conditions are ok, replace the water valve (located behind the freezer - the water supply tube coming from the wall attaches to it).
After replacing the water valve, make sure the freezer wall tube (it goes through the back wall of the freezer and empties into the icemaker) isn't plugged up with ice. You can do this by removing the smaller white plastic tubing (it extends up the back of the frig from the water valve) and blowing through it.
If it's frozen solid with ice:
Remove the white plastic tubing from the freezer wall tube.
Slide the freezer wall tube out the back of the freezer wall.
Run it under hot water.
Put it all back together again.
Make sure the icemaker isn't full of ice. If it is, remove the icemaker and melt all the ice out of it by running the ice mold under a faucet. Be sure not to get any water into the square back part of the icemaker where all the electrical stuff is.
Put it all back together.
There's an 80% chance it will make ice within 2 to 4 hours.
6. If, after 2-4 hours there is still no ice, replace the icemaker.