According to the Norwich City official handbook 1990-91 defender Jamie Southon from Romford was on Norwich City's books as an Associate Schoolboy but had not yet made the youth side (1989/90 season). Jamie transferred his apprenticeship to Southend United where he made a solitary league appearance in the 1992/93 season.

Like many other players, he drifted into football's non-league scene with clubs from his home area. Playing primarily now as a midfielder, Jamie spent time with Dagenham and Redbridge, Grays Athletic and Purfleet before playing in Hong Kong with Sing Tao.

On his return from the Orient (Hong Kong not Leyton), Jamie rejoined Grays Athletic before signing for Chelmsford City of the Dr Martens League Southern Division in November 1996. Jamie joined ICIS league side Enfield in July 1997 on a monthly contract but rejoined Purfleet two months later. He made 30 appearances (2 as substitute) in 1997/98 scoring 4 times as Purfleet finished 10th in the Rymans Premier Division.

Jamie appeared in the Daily Mirror on Thursday July 2nd 1998 to comment upon the sending off of David Beckham for England against Argentina in the World Cup. Jamie, a former Essex schoolboy teammate of Beckham's said "Even as a youngster he had an attitude problem. I played against him when we were just ten and he would get upset and even cry when things weren't going his way. Now that seems to have turned into a certain arrogance and petulance and I know that what's came out last night." But Jamie added "I know he will be absolutely devastated by what he has done. One moment he was on top of the world having just scored a superb goal in the World Cup and the next he is on his way down the tunnel after being sent off. I am very sympathetic. He will take some really terrible stick at football grounds across England next season because everybody blames him for last night."

Southon joined Ryman Leaguers Hornchurch in February 2003. In August 2004, he joined St Albans City on a three month loan spell as new work commitments limited his ability to make training sessions at Hornchurch. He has since returned to the trouble-stricken Urchins but moved to Cambridge City in May 2005. During the 2005/6 season, Jamie moved to Chelmsford City but in June 2006, he moved back to his hometown joining AFC Hornchurch.