The 29-year-old was one of 17 out-of-contract players at Odsal but is set to sign a new 12-month deal.
"There was interest from elsewhere but signing for the Bulls was definitely my first choice," Walker told the Bradford Telegraph & Argus.
"I absolutely love it here and have been made to feel really welcome from day one.
"While I would have liked a bit more security than a one-year deal, that is always going to be difficult with the club's one-year probationary licence.
"Hopefully they can now start signing up the other out-of-contract lads because there is already a really strong core of players here to build around."
Walker's deal was announced by new head coach Francis Cummins at a fans' forum where new owners Omar Khan and Gerry Sutcliffe spoke of their intention to buy back the lease on Odsal and vowed to spend up to the salary cap in 2013 despite agreeing to take a cut in central funding.