Hey Lele, I also happen to really like her! She's really pretty !
I don't remember the blue electric eyeliner, but here are some tips to get her more "casual" look.
I couldn't paste the text describing her makeup from the INSTYLE website (it wont let me copy!), but they are having a step to step guide on how to steal her look!
http://www.instyle.com/instyle/read/ask/st...,489470,00.html
Oh, I forgot, you have to suscribe to the magazine in order to check the website or be an AOL member........
But all in all, I can always resume what it is saying:
Mischa Barton: the o.c.
So buzz-worthy it's being heralded as the new 90210, Fox's So-Cal drama The OC has one thing its predecessor lacked: Mischa Barton. Scintillating on the small screen as Marissa Cooper, this beautiful young woman is not without her share of problems. Yet, in a world of limitless wealth, these don't include typical high school anxieties like what to wear (her book bag is a slouchy leather Chanel), making the most of that awkward period ("Mischa is so beautiful, we avoid sophisticated styles or she could end up looking like a supermodel," warns hairstylist Daniel Curet), or landing a boyfriend (current count: two). With its fast cars, faster lifestyles and Barton in the driver's seat, The OC is poised to take us on one incredible ride.—Suzanne Zuckerman
So here it goes:
Skin: Neutrogena Healthy skin face lotion, Healthy skin eye cream, luminosity added with a mix of Chanel bases (Voile universel in Vanille and Cannelle).
Blush:Tarte Pickled peach or Mac Cheek hue in Factory or No 302 from Anna Sui.
Eyes: Maybelline Great Lash mascara, Chanel Intense eye pencil in Graphite, and a series of shadows in pink, peach, and champagne shades like Bobbi Brown Pink Shimmer Brick compact, Mac Canton candy, Chanel multi effect in Air and Kitten from Stila.
Lips: A swipe of Lancome Juicy Tubes in Daiquiri.
Mischa Barton and The O.C.!!She always manages to look amazing no matter what she's wearing and her makeup compliments her so well! 
