I don't actually have aphids but I've always wanted to release a batch of ladybugs in the garden just because. It would be an awesome Eric Carsle happening... a yard full of grouchy ladybugs.
This is a great organic gardening supply. It may not be a "supply" per se, but you should certainly think about having some in supply. They're much easier than trying to attract predators with sunflowers or geraniums. And if you've ever tried planting garlic or chives in your soil to keep pests away, you know it can stink -- particular in container gardens.