Lockwood began his career as a trainee with Reading, after being released as a youth player by Leeds United. He turned professional in August 1999, but failed to break into the Reading first team and in 2000 joined Maidenhead United to gain first team experience. In February 2001 he joined Forest Green Rovers on loan until the end of the season. He appeared in the 2001 FA Trophy final for Forest Green but was on the losing side in a 1–0 defeat. In September 2001 he joined Yeovil Town on loan, a month later making the move permanent on a free transfer.