One of the best deals around zooms in for its annual landing this weekend at Constitution Hall, where the United States Air Force Band kicks off its Guest Artists Series of free Sunday concerts. E.G. Marshall makes a special appearance this Sunday to narrate Aaron Copland's "A Lincoln Portrait" and "Irving Berlin: A Man and His Music."

The concerts run through March 23 and will feature the likes of special guests Carol Lawrence, Richard Carpenter, Casey Kasem and Johnny Rivers. Throughout the series you can expect to hear the USAF Concert Band, symphony and string orchestras, Singing Sergeants and the Airmen of Note jazz ensemble. All concerts begin at 3; doors open at 2. DAR Constitution Hall is at 18th and D streets NW. Call 767-5658.

And as long as we're on the subject, there are two other free concert series worthy of note.

* Every Sunday through June, the National Gallery of Art presents a performance beginning at 7. This weekend, soprano Daisy Jackson sings music by Debussy and Handel. No tickets are required; seating begins at 6 in the West Building, West Garden Court, Sixth Street and Constitution Avenue NW. 737-4215.

* The Library of Congress is sponsoring weekend chamber music concerts throughout February beginning Saturday at 5:30 with "Music From Marlboro," a program featuring works for wind instruments by Beethoven, Mozart and Janacek. The library concerts -- to be presented each Friday at 8 by the Beaux Arts Trio and each Saturday at 5:30 by various artists -- are in the Jefferson Building's Coolidge Auditorium at First Street and Independence Avenue SE. Some tickets are available at the door, but it's best to reserve them in advance by calling 287- 5502 on the Monday preceding the Saturday concerts; reservations for Friday concerts can be made by calling on the preceding Saturday.