1941. If the reports cited below are to be believed, Seasick
Steve was 67 years old at the beginning of 2009. This suggests he
was born in 1941.
http://www.independent.co.uk/arts-entertainment/music/news/seasick-steve-sings-the-blues-for-a-brit-1452285.html
http://www.gigwise.com/news/49403/Seasick-Steve-Busks-At-Earls-Court-Tube-Station-Before-Brit-Awards