Thanks to my new membership of the Guild of One-Name Studies, I just discovered a couple of (legitimate!) web sites which reveal the popularity of a given surname.
The United States Census Bureau has a downloadable zip file containing all surnames with more than 100 entries in the 2000 Census.
RETTIE ranks =111,119 with 147 people.
Surnames of England and Wales – the ONS list is an extract of an Office of National Statistics database, and contains a list of surnames in use in England, Wales and the Isle of Mann in September 2002.
RETTIE ranks =28,353 with 128 people.
Unfortunately, I’ve yet to find a page providing surname statistics from the Scotland Census…not to mention Canada, Australia, etc. Does anyone have these URL’s?
UPDATE: Found a couple more sites, as a result of the course I’m currently doing:
Behind the Name
Though RETTIE was not found, it does return results for more popular surnames for USA, England and Scotland.
World Family Names
This site gives the frequency of a surname per million of a countries population.
RETTIE returns 6.02 for the UK, 1.83 for Canada, and 0.78 for USA.