Black plastic table cloths and pink sequin confetti- go to the party aisle at Wal-mart.
Or check out your local party supplies store and see what they have in stock that fits your theme and color.
Pink floating candles in little bowls- I'd go to my local St Vincent De Paul thrift store for the bowls.
usually when I'm dealing with a situation like yours, I just head over to the Dollar Tree (or other Dollar store) nearby and browse the aisles until something jumps out at me.
In your party store, the 40th 50th and 60th birthday sections will have lots of black, as well as some pink items. Pink would be easiest to find in a wal-mart or dollar store, just head to the little girls aisles. Another spot to check out for more elegant items would be wal-mart's craft department or a better craft store.
Good luck- just keep your eyes open and let the inspiration jump out at you from the store shelves.