Villa has been strongly linked with a move for Rangers goalkeeper Allan McGregor.
Houllier said: “In January, I don’t think I’ll make many moves because there will be many injured players coming back.
“I’ve seen Nigel Reo-Coker running this morning and maybe in two weeks’ time he’ll be back.
“I am also hoping Emile Heskey starts (training) with us on Monday or Tuesday.
“I also don’t want to buy what we have. It’s definitely in midfield where we need to buy one or two players.”