Leeds are currently without Richard Cresswell and Steve Stone with long-term injuries and Gylfi Einarsson is currently unavailable because of a three-match suspension.
Speaking to the Yorkshire Evening Post, Blackwell explained the current situation: "We're looking around to see what is available, but it's never easy at this time of year because clubs are always reluctant to release players.
"Everyone is in the same boat with injuries and suspensions looming. I've been quite hard on the scouting staff in that we need the right people for the right places and with the right availability. That's not always in their hands.
"There are a number of players we can bring in, but they're not what we are looking at and I only want the right players who can do a job for us."