SEVEN thousand pairs of eyes were focused on the stage of the Greek Theater in Los Angeles. The amphitheater was a cradle of excitement. As the orchestra began the overture, the spotlights came on and Liza Minnelli burst onto the stage. With a few steps from a jazz ballet, she danced toward the microphone.Wearing a white vinyl mini coat and hat, Ms. Minnelli shimmered under the lights. Without waiting for the applause, which was enormous, she started singing "The Nearness of You." By the chorus, she had reached into one of the deep pockets of the coat, and pulled out a pair of binoculars and began looking back at the audience. Minnelli must have recognized many in the first few rows - her step-sister Lorna Luft and Lorna's dad, Sid; Lee Minnelli, the widow of Vincent Minnelli; close friend Angela Lansbury; Roddy McDowell; Maggie Smith; Sidney Guillaroff, who had styled her mom Judy Garland's hair for years at MGM; Dudley Moore, her costar in "Arthur;" and more. It was quite a reunion. Minnelli calls New York City home, but for three months she was in Buffalo and Toronto filming a new Paramount musical, "Stepping Out." Then she immediately launched her concert tour. For 60 minutes she sang an autobiography of women's songs - falling in love, out of love, waiting for love, crying about love. Her voice at times was soft as a tear, other times it had the force of a trumpet. After intermission, Minnelli and her eight "Demon Divas" tap danced and sang for another hour. Later in her suite at the Beverly Hills Hotel, Minnelli spoke about what energizes her work. She said, "If you love what you're doing, it gives you the energy to do it. Also, it doesn't hurt to train like an athlete. "Before we opened at the Radio City Music Hall, we auditioned 400, and picked the eight most talented women I've ever known. I've dubbed them my Demon Divas, for each one can sing up a storm and dance the dust out of a stage." The divas are not an ordinary chorus line; they range from 16 to 60, and from 100 to 200 pounds. "We rehearsed the dances for eight weeks and built up our stamina for the tour," Minnelli explained, slipping her shoes off and settling into a chair. She relaxes where she can, for her heavy schedule is just beginning. The premiere of her movie, "Stepping Out," will be a Royal Performance in London. "With," Minnelli sparkled, "Princess Diana attending. "Next, I go to Paris for a month to perform with my great favorite, Charles Aznavour. We have to sing his 'There Is a Time,' and did you know he wrote 'Sailor Boy' for me? Then, the Divas join me for a tour of Europe, beginning with Stockholm." Minnelli will be in Las Vegas for New Year's and then at Radio City Music Hall for a return engagement in January where ABC-TV will tape a special of her concert. The Oscar-, Tony-, and Emmy-winning performer is riding the crest. Radio City Music Hall has invited her back twice in 10 months, and she's the first entertainer to sell out Carnegie Hall for three full weeks. "I did 'Stepping Out, she frankly admits, "because of director Lewis Gilbert." The award-winning director is responsible for such hits as "Educating Rita" and "Shirley Valentine." "Lewis has a knack for taking ordinary people in everyday situations and making them alive and passionate," Minnelli explained. "When I read the script, I loved it. First getting to work with him, and then because I get to tap dance. I play dancer Marvis Turner, who had 10 minutes of greatness as an understudy. Now, she's teaching a group of adults how to tap dance in a rented hall of a church. The students use the class as a break in their everyday grind. They start out to take tap, and wind up learning about life and each other. "Tap dancing is probably the happiest form of dance. During rehearsals, we had so much fun, and made so many mistakes, [director] Gilbert put many of them in the script. "We filmed in Buffalo and Toronto, using the interiors at St. James Anglican Cathedral, Toronto's oldest church. "My favorite scene is when I'm alone in the church hall. I've had it with my selfish boyfriend, my students who seem to have two left feet, and with life in general, everything. "Suddenly, it's like those dance solos of Astaire in an MGM musical. I do a few dance steps, then from nowhere the music begins, and suddenly I'm cooking. As I dance, I let all my rage, passion, and dreams spill out."OR Minnelli, the most important segment of the Los Angeles show was her tribute to her father, Academy Award-winning director Vincent Minnelli. "The movie screen came down on cue, but that's the only thing that went right. The film broke, the sound went out of sync, and I was devastated. I told them to stop the projector, and just then I heard the piano playing, and I began to ad-lib. I told the story about dad, without the sound or the songs." It turned out to be one of the best moments in the concert. "I remember my dad briefly mentioning working at the Radio City Music Hall. When I researched, I found he had designed the sets and the costumes for 10 years at the Chicago Theatre and Radio City. In their archives, I found wonderful sketches he did for the sets, which I showed on the screen. "I guess the best advice I ever received was from him when he said, 'Be prepared, then when the big break comes, you're ready. Minnelli still follows that advice, for seldom does a day pass when she doesn't take a lesson - voice, ballet, modern, tap. Another of her favorite tips was from Laurence Olivier. "In discussing acting, he said, 'Just don't get caught at it.' It's the same in real life. When something hurts, you don't make a big scene, you try to cover it up. In the movies, don't go waving your arms around, let your eyes reveal your inner feelings." "Stepping Out" is the name of her latest movie and record (the song was written by John Kander and Fred Ebb, who did "New York, New York,Liza with a Z," and "Cabaret"). It's also the name of her concert show. What does the phrase mean to Minnelli? "Was there ever a time in your life," she asked, "when you really had a desire to do something - even though it was new and you were afraid? Stepping out is to follow your instincts and move in a new direction even though it may scare you. To take a chance - and enjoy it!"