The first census after football turned professional was in 1891 – there are 408 listed in the 1901 census for England and Wales.
For England and Wales, you can access census records at the National Archives in Kew and online at various commercial websites. Regional census returns may be found at your local reference library.
For Scotland and Ireland, see the General Register Office in Edinburgh (also available online, for a fee, at www.scotlandspeople.gov.uk) and the National Archives of Ireland www.nationalarchives.ie.