Some women wear foundation every day, but I only wear it on special occasions. I like The Body Shop Nature's Minerals Foundation SPF25, $45 for 5g, which I have in 01, the lightest shade. It is available in five shades. I have also tried Bare Escentuals Foundation in Fairly Light. It's $78 for 9g, and is available in fifteen shades. I prefer The Body Shop one, because it is more mattifying, and it is a lot more affordable.
These are both mineral powder foundations, but there are a lot of natural liquid foundations available, like Living Nature Foundation, $49 for 30ml, and available in six shades.
Some other options:
Mineral foundation: Natio Mineral Loose Foundation 10g $23, available in three shades, Bloom Pure Mineral Powder Foundation 2.5g $39, available in three shades
Liquid foundation: Dr Hauschka Translucent Make-up 30ml $49, available in five shades, Living Nature Illuminating Tint 30ml $52, available in three shades, Aveda Inner Light™ Liquid Foundation SPF 12 30ml $73, available in twelve shades, Couleur Caramel Foundation Liquid 30ml $76.99, available in three shades
Cream foundation: Aveda Inner Light™ Dual Foundation SPF 12 7g $73, available in nine shades, Couleur Caramel Foundation Cream g $76.99, available in five shades