Need A Caterer
I'm not sure how high end you'd like to go but I think that Gai Klass is the best in the city - the food is just about flawless, the service is impeccable, and working with them is so easy. I've used her for (my work) two years now. And her finger food is absolutely delicious - anything and everything you could dream up... fresh potato chips with gorgonzola, buckwheat blinis with lobster and caviar, goat cheese quesadillas, sashimi, and many, many, many others.
On the other hand, you might just want to pick your favorite restaurant - it seems like so many cater as well.
I can unabashedly recommend our wedding caterer: the Santa Monica-based Fritto Misto restaurant. Extremely reasonable price, excellent food. They handled food for 80 people in Malibu in July with nary a snag. Ask for Melinda or Robert.
601 Colorado Ave
Santa Monica, CA 90401