"Attention, attention," shouted Muhammad Ali yesterday in New York, whence he'd come to ballyhoo his Feb. 15 title defense against tyro Leon Spinks in Las Vegas. "I have an important announcement.

"I have just signed a contract to fight (Ken) Norton for $12 million right after I get rid of Spinks.

"Twelve million dollars is outrageous," Ali went on. "Two million is a lot of money, but 12 - me, too."

By "right after" Spinks - assuming Ali, who turns 36 in January, gets past the 1976 Olympic champion, 24 - he means along about September.

Norton has not agreed to terms for his fourth fight with Ali, according to Bob Arum to Top Rank, Inc., promotor of both these upcoming heavyweight clashes. The autumn bout will be staged overseas - speculation centers on Iran.

Arum and CBS -TV supposedly were caught unawares and dismayed by Ali's announcement overshadowing the unfinished Spinks business. Arum said the word wasn't supposed to be issued until Feb. 16. But the World Boxing Council, and Norton, who had taken his plea to WBC in Madrid recently, must feel like winners because the champion more or less is living up to the demand he signify by Jan. 6 that he would negotiate for a Norton rematch . . .

Fears by Bill Wrigley and company that he might have to sell the Chicago Clubs have been alleviated by preliminary appraisals that other assets of the estate of the late Philip K. and Helan Wrigley should be sufficient to cover the inheritance taxes. Some estimates placed the chewing gum-based Wrigley fortune near $100 million, of which the tax collectors might grab $70 million in the wake of the deaths of Mr. Wrigley in April and his wife in June . . . But who needs a baseball team? Under a default judgement issued in U.S. District Court, San Diego, this week, the Padres might be liable for some of the $17 million lost by minority stockholders of the failed bank that the team's former owner, C. Arnholt Smith, headed. And if that didn't ruffle Ray Kroc, his McDonald'd Corp., prodded by a stockholder's complaint, is investigating allegedly excessive use of company airplanes and other assets by chairman Kroc . . .

Coach-go-round: U. of Wisconsin athletic director Elroy Hirsch names a football coach today and one report has Navy's George Welsh "belived out of the runnings." Welsh said Hirsch interviewed him Monday in Madison - "They contacted me first, but I did tell them I was interested."

On the local fight front, the Starplex promoters may be billing D.C.'s Johnny Gant as world's 10th-ranked welterweight, buRing magazine had dropped Gant from its top 10. The SUnday Express, "the national newspaper of Trinidad," was aghast at Gant's performance on the Caribbean island last month when Eddie Marcelle of Trinidad decisively outpointed him. "Hard boiled ringside gamblers were giving 3-1 on Gant" wrote the Express' David Brewster, "but they were stunned time and again when the Trinidadian beat the 27-year-old world rater to the punch." Gant blamed recently inactivity. Marcelle - who had Angelo Dundee in his corner - tole the home paper he would soon be "returning to Dundee's gym in Miami, where he will be doing regular sparring sessions with Sugar Ray Leonard" . . .

Gant's 10-rounder with Freddie Boynton of New Jersey is the closer on Saturday's D.C. Armory card, on which the opponents for two more locals were changed yesterday. Light-heavy Biff Cline now will meet Dave Dittmar of Philadelphia and middle-weight Keith Broom will fight Tyrone Ffreeman of Philadelphia in six-rounders on the Leonard Hector Diaz undercard. Broom - being handled by Don Angell, who has some good ameteurs we haven't heard much about at his Annandale Boxing Club - recently turned pro after a distinguished amateur and Navy ring career capped by the 1977 national Golden Gloves 165-pound championship. He's moved up from North Carolina.

Angell swears Broom "Beat Leon Spinks in Olympic box-off at Burlington, Vt." Maybe gold-medal brother Michael Spinks? . . .