Spring underwent a medical this morning and Blackwell was delighted to welcome the midfielder to the club.
Blackwell said in the Yorkshire Evening Post: "I'm pleased we've been able to agree things with Springy. He is a good, strong midfielder who isn't afraid of putting his foot in. He is the sort of player we need in this division. He's got good desire and he's hungry to play here.
"When I spoke to him we never talked about money. That was never an issue because he just wants to play for Leeds. Joe Kinnear worked with him for a few years at Luton and wanted to take him to Forest. He knows all about him and the fact he was keen to sign him speaks volumes."
Everton are still showing interest in the 28-year-old Wright so Leeds were refusing to confirm anything until he formally puts pen to paper on a proposed three-year deal.
He is available on a free transfer after rejecting Ipswich's latest offer and Leeds hope to sign him subject to a medical.
The pacy, strong right-winger, who can also play at full-back, was a consistent performer for Ipswich last season, making 48 appearances in league and cup competition.