Where does a props person go to find a Western Electric double-button carbon microphone, circa 1927? Why, to Bob Paquette's Microphone Museum in Milwaukee, of course.

That's what Sandra Fleishman, resident props mistress for the Studio Theatre, eventually learned during her mission to realistically outfit the current production of "Ma Rainey's Black Bottom," a play set in a seedy old-time Chicago recording studio.

"I'm not the world's greatest builder," says Fleishman, "so the idea of having to make all those things kind of terrified me."

Fleishman's exhaustive search led her to Elliot Sivowitch of the department of electricity and physics at the Smithsonian's Museum of American History, who did what any other electricity buff worth his current would have done -- directed her to Paquette's legendary mike museum. (Fleishman also obtained authentic radio equipment from Ed Lyon of the Mid Atlantic Antique Radio Club, a Laurel-based group that has 175 members, including one in Australia.)

"It's not the kind of place the average person off the street would be interested in," says Paquette of his museum, which shares the same building with his commercial sound system business. (He also restores Model T's and teaches gymnastics and swimming on the side, but that's another story.)

Though Paquette's museum will never set any attendance records, he can take satisfaction in knowing that it is home to the world's largest collection of vintage microphones (some 800 of them, the earliest dating from 1876) -- serving as the mecca to a small but intense circle of microphone aficionados (Paquette says he still gets calls about a 1974 Audio magazine article he wrote titled "Mikes of the Pre-War Era").

Some of Paquette's mikes have even gone Hollywood, costarring in films such as "City Heat," "Raging Bull" and "Zelig" right alongside Clint and Bobby and Woody. He's paid a fee by film companies for use of his microphones but charges theaters only shipping costs.

"Generally, these theater things are kind of hairy," concedes Paquette. "They don't always work out. Sometimes they don't send back the mikes."

Such experiences, he says, have left him "a little bit skeptical" about lending out his microphones for artistic purposes. He continues to do so, but now he parts only with those mikes he has duplicates of. Development Delay

A blue-ribbon committee for the promotion of the arts and economic development that Mayor Marion Barry said three months ago he would establish has yet to be named. At a Feb. 28 press conference announcing his request for $1.7 million in the fiscal 1987 budget to start a program for construction and renovation of arts facilities in downtown Washington, Barry appointed Kwasi Holman, executive director of the Office of Business and Economic Development, to head the committee. Holman said at that time he would name the committee within two months. "We're very close to announcing who's on the committee," a spokesman for Holman said last week. "But I couldn't say definitely when." Living Stage

Washington theatergoers will have a rare opportunity to see performances by Living Stage, the outreach theater company of Arena Stage, which ordinarily performs only for special groups, including disabled children and teens, inner city students, the incarcerated and the mentally disabled. Living Stage will present "Images," which concerns a disabled teen-ager who confronts the prejudices of an able-bodied world, and "Longstreet," which explores the issue of war and its effect on teen-agers, at its theater at 14th and T streets NW this Friday and Saturday and June 6 and 7 at 7:30 p.m. For information call 554-9066. Odds and Ends

Friday's performance of "Ma Rainey's Black Bottom" at the Studio will be a benefit for the theater. Tickets cost $100, which includes a postperformance champagne reception with the cast and the theater's board of trustees; call 298-2500 . . . "Twelfth Night" begins previews tonight at the Shakespeare Theatre at the Folger . . . "The Taming of the Shrew" opens Thursday at the Arena . . . "The Caine Mutiny Court-Martial" begins a six-week run Thursday at the Kennedy Center's Eisenhower Theater.