Toshack says James will be remembered as fondly in Burnley as Wales after three spells with the Clarets.
“The success Leighton had there with them and the goals that he scored, I’m sure that the supporters will be remembering those goals for a long long time to come,” Toshack added.
“There will be a lot of sadness in that area of Lancashire because he was an incredible talent.”
Swansea and Wales legend Alan Curtis said James “was a great player”.
Curtis added: “That word is often given to good players, not great ones, but Leighton was a genuinely great player.
“Even to this day I don’t know if he was right or left-footed. He was a terrific player.”
Wales forward Ian Walsh says James is a huge loss to Welsh football.
“Apart from being a wonderfully technical footballer, he was an imposing character,” he said.
“I had some really funny moments and some great times with him as a team-mate.
“His style of wing-play is a skill that has gone out of the game.”
BBC Radio Wales and Sport editor Carolyn Hitt also paid tribute, saying: “Leighton was a familiar and popular contributor to the BBC Sport Wales.
“Our sincere condolences go out to his family and friends at this time.”
