Croft, 21, looks set to make his debut for the Canaries in next weekend's Championship opener at Elland Road. He completed a medical and agreed terms earlier this week before yesterday deciding his future lies in East Anglia.
"I came down last week to meet the Manager and have a look around and I was really impressed with the facilities and the Club in general," said Croft. "I can't wait to get everything sorted out and then join the rest of the lads for training in the build-up to the game at Leeds."
Croft, an England under-19 International, made 32 appearances for Manchester City, scoring one goal. He also had a spell on loan at Oldham in the 2004-2005 season.
"The right side of midfield is an area we've been trying to strengthen for two years now and I'm delighted that Lee has now agreed to sign for us," was the opinion of Nigel Worthington, who believes the player will add a new dimension to the side's attack. "He will be a huge asset to us with his direct style, his pace and his general approach to the game."