It helps to pay attention to your posture, like when you are driving, try to relax your shoulders and relax your head back against the headrest. Also go to a drugstore that sells orthopedic supplies and buy a good soft collar neck support and wear it around the house and while you are on the computer or even at work if you have to. While you are there, get a Thermaphore heating pad--it has been a lifesaver for me. It gives you a moist heat treatment.
I bought this little battery-powered neck massager and keep it on the coffee table and give myself a buzz every hour or so when I'm watching the tube in the evening. Also Icy Hot patches help. (Can you tell I have the same problem?) There is a product called Bio-freeze that is good. too.
I try to stay stretched troughout the day so my neck doesn't "lock up" by doing head rolls and shoulder rolls every 1/2 hour or so and even bending over and doing a toe touch or 2 and then a sky touch. If you do a job like working at a computer all day, that's the worst for neck and shoulder pain.
Capt Deb