Moore began his career at Tranmere Rovers, where he broke into the first team while still a teenager, and made more than 50 appearances. He also spent a short period on loan at Bradford City to gain more first team experience. His impact on a Tranmere side that at the time was a regular contender for promotion to the Premier League, where his records for goals and assists and all-round contribution to play were impressive, along with his inclusion in England youth sides at all levels up to under-21s, led many to believe he was destined to play at an even higher level.
He made his first big-money move in March 1997 in a £1million move to Nottingham Forest under Dave Bassett but failed to make a significant impact – getting just one goal in 15 games and so was loaned out again, this time to West Ham United. Moore was given little chance at the Boleyn Ground and made just one substitute appearance.
Stockport County was the next team to take a gamble on the goal-shy striker who signed him for a club record fee of £800,000. To some extent the gamble paid off and Moore gave a goal return of almost one goal in every four games – netting 20 times and becoming the club's leading scorer.
This rapid improvement in form brought the attention of north west neighbours Burnley and Thomas-Moore moved to Turf Moor for a £1million record transfer fee in the winter of 2000.
Moore became known at Turf Moor for his pace and dedication, and regularly chased down goalkeepers and defenders to try and force mistakes. Moore went on to make almost 200 appearances for 'The Clarets', scoring 37 league goals in the process. He seemed to enjoy the FA Cup most though – netting a hat-trick against Canvey Island and a double against Bournemouth. Some of his fans said he was like a "dog with a balloon".
As his career progressed at Turf Moor, Moore was increasingly played as a winger, to take advantage of his pace. This was not a position which Moore enjoyed though, and he often visibly 'sulked' in games, and his previous determination had gone. Whilst at Burnley he also suffered a series of injuries which, while not career ending, were severe enough for the previously quick striker to lose much of his pace.
In the last year of his contract, Leeds United decided to sign the striker, where he re-joined the ex-Burnley assistant manager, Sam Ellis. Moore was sold by Steve Cotterill for a fee of £50,000, an amount many Burnley fans were surprised at due to the player's loss of form. Moore hardly featured under manager Kevin Blackwell with many Leeds fans seeing Moore as a waste of time and space. However, on 19 September 2006 in the League Cup game against Barnet, Moore scored his first goals for Leeds United, netting twice to lead the team to a 3–1 victory.
Under new manager, Dennis Wise, Moore played regularly and looked a completely new player. He scored his first league goal for Leeds United against Southend United at Elland Road and later scored against Stoke City too. However, he was released at the end of the season following his club's relegation to Leage One.
Moore signed for Hartlepool United on 12 July 2007, on a free transfer. But aftr nine goals from 30 appearances in all competitions he was transfer listed by the club in January 2008.
On 31 January 2008 Moore joined his father Ronnie when he signed for Tranmere Rovers for an undisclosed fee. He scored on his debut against his former club Leeds United in a 2–0 Tranmere victory. He also netted against Millwall and Port Vale as he ended the season playing up front with Chris Greenacre. Moore continued his good form against old club Leeds by scoring in a 2-1 home victory in the 2008/09 season
He ended up having an impressive season for Rovers, he scored 11 times as Rovers finished 7th and were two minutes away from clinching a play off place. Thomas-Moore scored a quality double against Carlisle in Rovers' 4-1 win. He also added goals against the likes of Stockport, Southend and Oldham as well as gaining a goal of the season candidate with a volley against Scunthorpe in the Johnstone's Paint Trophy.
Thomas-Moore had another impressive season at Tranmere in 2009/10 season, having netted 15 goals, including two penalties against League One leaders Norwich City in a surprise 3-1 victory at Prenton Park. He scored his 100th football league goal against Norwich. Moore also netted against Southampton, Gillingham, Wycombe and Aldershot.
Moore's impressive season went all the way to the last game of the season away at Stockport County. Moore scored the 2nd goal in possibly the biggist game of his career. Either way if Thomas Moore decides to stay at Rovers or leave in the summer the striker will go down as one the the all time favorites at Prenton Park.