Houllier is preparing for his first derby against Birmingham on Sunday without several key players through injury and suspension.
Skipper Stiliyan Petrov and striker Gabriel Agbonlahor are sidelined through injury, while fast emerging winger Marc Albrighton is suspended after his red card against Burnley in the Carling Cup.
Houllier is not a big fan of the January window but acknowledges he will need to add new blood.
He said: "I don't like January because January is not a good period. But you need to be blind not to see that there are some areas where we are not blessed with numbers.
"If we spot a really good player with internationally-proven experience who can bring something to the team, particularly in some areas, we will take him.
"We need to bring some players in. That's it. I think we will have one or two coming in January. "Will it be up front? Not necessarily."
Houllier is aware of the passion generated by a derby but stressed the need to concentrate on playing football at Villa Park.
He is also expecting the same response from his long-time friend and Birmingham manager Alex McLeish.
He said: "I had the Lyon-St Etienne derbies and the Liverpool-Everton derbies. I know the importance of the derby for the fans and the players. The players talk about it, which is good.
"All I know is that we need to play our football. At the end of the day, it is a game of football.
"Knowing their manager very well, I don't think he will pump up the players to do anything but just play football.
"The more fiery it becomes, the more composure you have to give. The derbies also shows a lot about the character of your players. I very much like the mental attitude of the players."
Villa have won only one of their last six Premier League matches but Houllier is happy with the level of performance.
He added: "I don't think our defeat against Tottenham or Sunderland should make us blush. The performance levels have been better than the results. That is the message to the players."
Villa have triumphed in the last six meetings with Birmingham, three of them with McLeish in charge.
But Houllier feels that record will have little bearing on Sunday's noon encounter.
He said: "The past is the past, whether it is players or results. It is a different era.
"We are looking forward to this derby. Don't make reference to the past.
"That is always the message to the players. The most important game is the coming game, and that's the derby."