Valerian Ruminski, the globe-trotting Buffalo-born bass-baritone, is gearing up for next weekend’s “The Barber of Seville”—the inaugural production of his long-awaited Buffalo opera company, Nickel City Opera. As the big day nears, a variety of exciting and offbeat events will benefit the troupe. On Saturday night, composer Persis Vehar joins Ruminski in Nietzsche’s (248 Allen St.) for a Bukowski Beer Drinking Cabaret. They’ll perform Vehar’s songs set to the words of barfly poet Charles Bukowski. “Bukowski loved classical music,” Ruminski says. “The evening will be in his spirit of bold, plain speech elevated to song, with a dash of rowdiness thrown in.” The cabaret starts at 7 p. m. and runs until 10:30 p. m. At 6 p. m. Monday in Ilio DiPaolo’s Restaurant (3785 South Park Ave., Blasdell), a grand Italian six-course dinner features up-and-coming singers singing arias after each course, with a grand finale ensemble performance. The $45 cost includes tax, gratuities and wine toast. Call Sylvia Volk, 881-1424. At 7 p. m. Wednesday, Ruminski and Nickel City Opera singers will be on hand for a dinner, complete with music, on stage at the gloriously restored Riviera Theater. Tickets are $50. Call the Riviera, 692-2413. It all peaks with Rossini’s riotous “The Barber of Seville.” Nickel City Opera’s first production, presented in conjunction with Ottawa Pocket Opera, will take place at the Riviera Theater at 8 p. m. next Friday and 2:30 p. m. June 28. Admission is $20 to $50. For tickets or information, call 692-2413. —Mary Kunz Goldman