Let me reiterate the point that you should not try to match your eyeshadow to your eye color! This only dulls the beautiful color of your eyes, and in the case of you blue eyed beauties, just makes you look like you were caught in that really awkward makeup period between the 70s and 80s.
Thus, your signature colors are: rich warm browns, warm taupes and soft peaches. (If you are a fair blonde with blue eyes, violets will also work well for you.) Make sure you go with a rich, deep brown if you want to achieve a more dramatic and impacting look. Sorry to use more shades from MAC, but here goes:
Step One: use Motif on lids and lightly on the brow bone (underbrow region)
Step Two: use Amber Lights (or a LIGHT application of Espresso) in the crease
Step Three: blend
For a dramatic eye
Step One: use Amber Lights on the lids
Step Two: use Motif on the underbrow region, in a slightly heavier application than for the everyday eye
Step Three: use Espresso on the crease and blend into the corners of the lid
Step Four: continue to blend until shadow appears fluid
(Use your favorite dark brown liner to complete this look.)
If on a tighter budget, Almay provides a lovely option:
I also think that Covergirl's Eye Enhancers 3-Kit Shadows in Cafe Au Lait (or, if you fall into the violet category, Dance Party) is a wonderful option.
Have fun and rock those baby blues!