When you want a slightly-smoky look à la Ash Greene, try Dior Crayon Kohl Eyeliner. Available for $29 at Sephora.
To make your eyes look bigger, focus the color on the outer corners and keep the inner area clean like Keri Russel did here. A great product to use for this technique is Guerlain's Terracotta Loose Powder in Kohl since it's a loose powder that can be applied as an eyeliner, allowing you to layer more color where you want it. Available for $37 at Nordstrom.
Cara Delevingne proves that when you want a drop-dead-sexy look you go for a smoldering, smudgey eye and vampy red lip. BECCA's Ultimate Crème Eyeliner is actually a three-in-one eyeliner that acts as a cream liner, a kohl liner, and an eye shadow, which means Cara's eyes will be yours in no time. Available for $20 at Sephora.
Even low-makeup-maintence Kristen Stewart can get involved with a liner that creates this look in less that five minutes. Try Rimmel London Scandal Eyes Waterproof Kohl Eyeliner, available for $4.50 at Ulta.com.
To get Minka Kelly's sexy style, line both the waterline and top lash line with Jane's Water-Resistant Liquid Eye Liner in black. Available for $8 at Janecosmetics.com.
Applying a thicker black line up towards the crease and blending into your shadow will give you that Olivia Wilde hotness. Try Palladio Ultra Bold Eyeliner Marker, available for $8 at Palladiobeauty.com.