Makeup brushes tend to be overlooked, perhaps because many makeup products include a puff or brush or some sort of applicator. As poor quality as some of these applicators are, many women balk at the idea of buying separate tools -- the brushes that come with the products are smaller and more portable, and good brushes can indeed be pricey. But here's a good line I read recently: Your skin is like a delicate piece of silk. Your makeup brushes shouldn't feel like they are brooms sweeping across your skin. Quality brushes also will make applying makeup easier, faster, and more pleasurable, because they are made in specific shapes and sizes for the job at hand (e.g., blush brush, powder brush, eyeshadow brush).

Before purchasing a brush or brush kit, check that each brush head is soft and full. Run your hand through the bristles. It is a bad sign if they come out readily/shed or feel coarse on your skin. The handle should feel comfortable and seem solid. Keep your brushes in a protective case or upright in a decorative glass or container on your dresser, not in the bathroom, where moisture accumulates. Every few weeks, or at least once a month, gently wash them in a mild liquid detergent or baby shampoo. Do not soak them. Pat each brush dry, especially around the area where the brushes meet the handle, and lay them flat over the edge of a table or counter so that the bristles are open to air on all sides, and reshape the brush head.

I'm not endorsing this brand, but BareEscentuals offers a good selection of brushes. Take a look simply to see what shapes and sizes of quality brushes are available, and their cost.