Get a Kegelmaster2000, it will change your life! Not only will take care of the incontience but it will dothings for your sex life that you just won't believe. You can order online or probably get at an adult store. If you don't have a vibrator then either buy one or get the Kegelmaster that comes with a free "second" device. You'll need it the first few times you use the Keglemaster to help you be certain you are using the right muscles. Using your abdominal muscles may not help and might make some problems worse. Just doing kegels isn't enough to resolve this, you need the resistance of the device. Losing weight and doing some general fitness work will help too.
I lost 40 lbs, took up running, ate a healthy diet and have done kegels for years but while those helped, I still had trouble with sudden and frequent urgency. With the Kegelmaster I've got it under control and then some. They cost about $100 and are worth every penny. The added bonus is that you will be as tight (or tighter) as you were before you had kids and have some great muscle control. You and your partner should find that your sexual responsiveness goes up several levels!