See information about The Art of Science and an interview with me here.
If a story has a historical setting, or perhaps the writer wanted to know the name of a character would have been used or even common for a particular age group, the social security administration has kept some records since the 1890s.
Since 2000, they have detailed records of the top 1000 names for both male and female babies born in the US and some data about popularity by state. Data includes ranking with some statistical information about how probable the name is to find. If nothing else, it’s interesting to play with just to see how things change (like the fall of Emily from the number one slot this year to Emma – my, how similar they sound).