Webber is a free agent while Stead has fallen out of favour at struggling Ipswich.
But Warnock, who has ruled out signing the pair, has revealed he is stepping up his search for a forward after finding out Stern John will not recover from his dislocated elbow until the end of next month.
He told Your Local Guardian: "I spoke to him (Webber) last week but he rang me for advice more than anything. We want a big guy to go up front really.
"We can't afford Jon Stead. I don't think we will be doing anything this week but we are still on the lookout for a striker with Stern John out until the end of October."