So. I have been asked to make a three tier topsy turvy cake. Among the colours she wants pink,black& turquoise. Not being "artsy" I am not sure what colours to put together so that it looks good. Is there a colour chart somewhere that shows what colour corresponds with another?

There is no right answer. However, a color wheel from an art supply store(or look on line) can be very helpful in choosing the best complimentary or contrasting colors.