not sure if there's anything like this for the UK, but the US has lists (by year) for all baby names used since 1880. Any name that was used more than 5 times that year is on the list. Just looking through it for 2009--5 boys were named kingdavid, 5 Willliams, 583 Kings. It's pretty neat.
You can grab the file here
www.ssa.gov/OACT/babynames/limits.html