My parties usually include some mutant form of devilled eggs (one year with chipotle, one with wasabi, my last one used lots of lemon juice to attempt an avgolemono taste, it was less than successful at that, but still was eaten).
Smoked salmon (inexpensive at Costco), with creme fraiche (seen in Jewel, but you can just leave cream (not ultrapasteurized) out to sit for a day with a couple tablespoons of buttermilk in it and it should thicken right up) chives and any number of starches to hold it with (phyllo cups, rye, toast points, blinis, etc. etc.). Add chopped egg, caviar, capers etc. for garnishes.
Kosher mini hot dogs wrapped in small pieces of Pillsbury crescent dough beat the snot out of commercial bagel dogs.
A cheese platter never hurts, and is nearly effort free.
Wonton or gyoza wrappers, frozen puff pastry and phyllo are great secret weapons. Phyllo-based treats will take some effort, but with big payoffs. The wonton wrappers can be used for ravioli, pot stickers, pierogies, crab rangoon...
Some books I recommend:
Cooking Under Wraps by Nicole Routhier -- outstanding book, not a bad recipe in the bunch. Not all hors d'ouvres, but all flavorful and beautiful dishes.
Martha Stewart's Hors D'ouevres Handbook (couldn't get URL to work) - nearly encyclopedic and full of food porn. Her recipes usually take more steps and bowls than really neccessary, but have some great ideas for building a party platter around a few variations on a theme.
What is patriotism, but the love of good things we ate in our childhood?
-- Lin Yutang