Hey Julie! I've catered a few events and the following have gone over very well. They are all pretty east too (very important to me!) One hint - the ever popular shrimp can get expensive. Think of using it as a part of something or a garnish rather than a shrimp cocktail. Also - it's all the presentation. A bowl of tuna salad is run of the mill but put it in a hollowed out red cherry tomato with a parsely garnish on a fancy platter and that's something to think about!

1. cherry pepper antipasti: hollow out mild cherry peppers and fill with a piece of provolone and salami (can broil to melt the cheese or serve room temp)
2. filo triangles: mini filo triangles with a variety of fillings - spinach, pine nut & feta; ratatouille & goat cheese; roasted vegetables & mozzarella or meat fillings (can make ahead and freeze, best served warm) These are easy but take a little practice as the dough is delicate and dries out very quickly. Just follow the directions on the box and be prepared to screw up the first few until you get rollin'.
3. Insalata Caprese on skewers: fresh mozzarella (either chunks or the smaller balls if you can find them) and cherry tomatoes (yellow/red mix is nice) threaded on wooden skewers, drizzed with a vinaigrette & fresh basil (room temp. fine - super easy)
4. Roast Beef Canapes: mini bread rounds spread with a mixture of sour cream and horseradish, small piece of rare roast beef on top and garnished with radish and a sprig of watercress. Elegant and couldn't be easier.
5. Skewers - anything on a skewer is easy to eat and looks pretty cool. Think satays (thai chicken with a curry sauce), greek lamb meatballs with a garlic yogurt sauce, roasted vegetables, tortellini of varying colors with a vinaigrette, fresh fruit with a poppyseed or yogurt dip, etc. Fine hot or room temp.
6. Round slices of roasted red potato topped with a dollop of sour cream, a dab of caviar and a sprig of dill. Supermarkets carry inexpensive and certainly passable caviar and this makes for an easy and impressive offering. It's just meant as a garnish anyway. Looks especially nice is you use both the black and red caviar on a tray. Or if you want to get real fancy, make mini blini instead of the potatoes. Room temp fine.
7. The Italian antipasti set-up is always popular - platters of roasted vegetables, cheese, salamis, hot and mild peppers, olives, toasted nuts, etc.
8. Potstickers have become very popular - can buy them in bulk in the freezer section of most club stores now. Best served warm. Serve with a tasty sweet & sour sauce or a dipping sauce made of soy sauce, rice vinegar, sesame oil and a little chili sauce.
9. Tuna salad in a hollowed out cherry tomato. Or chicken salad on a cucumber slice. Smoked salmon on a cucumer slice with a caper and dill garnish.
10. Proscuitto or salami wrapped around melon or asparagus spears.
11. Hummus piped into endive spears.

That should give you some ideas anyhow! Good luck!