POP ROCK Larry Groce: ''Medicine Man.'' (Broadbeach 7) - No nonsense here. Just warm, gracious folk-rock from a sparklingly talented musican-singer-composer. It's Larry Groce, up close, personal, and welcome. Groce is past and present. Although his brand of music would fit more comfortably into an earlier era of rock, it's also as timeless as a small-town folk concert. Larry Groce on record doesn't glow with quite the magic of hearing him in concert, but it's close enough. His is a talent that doesn't need to be propped up in a studio with engineering wizardry. Take ''It's Magic,'' for instance, from Side 2. There's a musical excitement here that's so infrequent in popular music today. It's made up of honest, clear acoustic and electric guitar work, a voice that's malleable to the mood of each phrase, and sensitive, melodic songwriting. All this is embodied in ''It's Magic.'' True, Groce reprises certain very familiar themes: the man on the road longing for his sweetheart; words about a woman with a magical something about her. But these themes sound at once fresh and classical in the hands of Groce. Groce, and his accomplices - who include Cornelius Bumpus - deserve applause. ''Medicine Man,'' the title cut about what seems to be a man in the American Indian tradition, resounds with crisp vocals and instrumental work. My favorite among the songs is ''When the Mist Clears Away,'' with its encouraging message for people struggling with rugged times.