I've had a couple of hits in the last day or two looking for information about the Warsaw Concerto. I'm not sure if I've ever mentioned that work here, but I must have if I'm turning up in search hits on it. Anyway, the Warsaw Concerto is actually a work of film music, written by composer Richard Addinsell (1904-1977) for the film Dangerous Moonlight (released in the United States as Suicide Squadron), a World War II-era melodrama. Apparently the main character is an amnesiac pianist and composer, who spends the film recalling bits of the concerto he was composing before his memory loss; that work is the Warsaw Concerto. Addinsell wrote the piece after the film's producers decided not to pursue using Rachmaninov's Piano Concerto #2.
I own two excellent recordings of the Warsaw Concerto (and I'm sure more exist). The work is included in the Erich Kunzel/Cincinnati Pops Orchestra compilation disc, Victory At Sea and Other Favorites, a disc of music from World War II era films. This is one of my favorite CDs, actually -- the sound is spectacular and the performances are muscular and first-rate. Other selections on the disc include five selections from Victory at Sea (music by Richard Rodgers), a suite of Max Steiner's score to Casablanca, the lush theme to the TV miniseries The Winds of War, and others. The pianist on the Warsaw Concerto is William Tritt.
The other recording of the Warsaw Concerto in my collection is a Naxos CD, Warsaw Concerto and other Piano Concertos from the Movies (RTE Concert Orchestra, conductor Proinnsias O Duinn, pianist Philip Fowke), available on Amazon here. The focus on this disc is not World War II music but, as is clear by the title, works of film music featuring piano and orchestra. Other works here include Miklos Rosza's wonderful Spellbound Concerto and Bernard Herrmann's Concerto Macabre (from Hangover Square). The Naxos CD has the benefit, as do all Naxos CDs, of being budget-priced.