They say that it's normal for your dog to still smell of skunk when he gets wet for up to a year or so after being sprayed.
In my experience, tomato juice doesn't work. It just makes your dog a pinkish colour. I've also used a product called Orange Peel, it works okay, but there is still a bit of skunk smell left over.
I've found the hydrogen peroxide/baking soda solution works the best out of anything I've tried. I use 1/4c of hp, about a cup of baking soda, a squirt of dog shampoo and a couple of cups of warm water. I use a sponge or cloth to blot it onto the problem areas, let sit for around 5 minutes, thoroughly rinse then shampoo.