Heel and toe is something that needs to be approached much more consciously and cautiously in a front wheel drive vehicle. As stated so eloquently by killermonkeys, underrevving during heel and toe should be enough to lock your drive wheels.
Locking one's wheels results from the amount of force caused by the car's motion being so great that the tires slip across whatever surface they are usually rolling against. In a rear wheel drive car this would mean your back end slides across the road. However in a FWD car, this means that you've just killed all the traction in the wheels you also use for steering, resulting in nasty understeer.
There are still ways to slide one's back end in a FWD car, either by liberally abusing the handbrake, or by engaging in some left foot braking. During a properly executed handbrake turn you can still slide out your back end, having a higher tire pressure in front than in back will help with this. Judicious use of left foot braking can be used to slow and lock the back wheels while still maintaining some spin up front. Of course either of these activities qualify as some advanced driving techniques and not something to be engaged in lightly.
Interesting note: During the mid-eighties, Audi had designed their cars so that the brake and gas pedals were conveniently located for heel and toe driving. This resulted in one woman who did not understand how to drive her car mashing the gas pedal when trying to brake. The effect, instead of being classified as an example of stupid human tricks was instead labeled unintended acceleration. 60 minutes had a field day with the story, painting Audi as the devil.
Audi sales plummeted and the car manufacturer enjoyed dismal marketshare in the U.S. until the mid-nineties.