The following selections were found in iTunes for
Glenn Miller "I Know Why":
| Title | Artist | Album | PURCHASE |
| I Know Why (And So Do You) | Glenn Miller and His Orchestra | Memphis Belle (Original Motion Picture Soundtrack) |  |
| I Know Why | Glenn Miller and His Orchestra | In the Mood | |
| I Know Why | Glenn Miller | Ultimate Big Bands Glen Miller, Vol. 1 | |
| I Know Why (And So Do You) | Glenn Miller and His Orchestra | 1941 In Real Hi-Fi Stereo (Live) | |
| I Know Why | Glenn Miller Orchestra | Moonlight Serenade | |
| Sun Valley Serenade: I Know Why (Warren / Gordon) [feat. Lorraine Elliot, John Payne & The Modernaires] | Glenn Miller | Sun Valley Serenade / Orchestra Wives - Glenn Miller In the Cinema | |
| I Know Why (And So Do You) | Paula Kelly, The Modernaires & Glenn Miller Orchestra | Glenn Miller Orchestra Part 2 | |
| I Know Why | Glenn Miller & Paula Kelly & The Modernairs | Just One of Those Things | |
| Final Medley; I Know Why, At Last , The Kiss Pollka , It Happened in Sun Valley | Glenn Miller Orchestra | Sun Valley Serenade, Orchestra Wives (Great Movie Themes) | |
| I Know Why | Glenn Miller | 100e Anniversaire | |
| I Know Why | Glenn Miller & His Orchestra feat. Paula Kelly & The Modernaires | The Glenn Miller Story Vol. 11-12 | |
| Theme I Know Why | Glenn Miller and His Orchestra | Sun Valley Serenade, Orchestra Wives (Great Movie Themes) | |
| I Know Why (And So Do You) [Remastered] | Glenn Miller | The Fabulous Glenn Miller and His Orchestra | |
| I Know Why | Glenn Miller | Master of Swing | |
| I Know Why (And So Do You) | Glenn Miller and His Orchestra | Popular Recordings | |
| I Know Why (And So Do You) [From "Sun Valley Serenade"] {Remastered - 1994} | Paula Kelly, The Modernaires & Glenn Miller and His Orchestra | Falling In Love With Glenn Miller | |
| I Know Why | Glenn Miller and His Orchestra & Harry Warren | The Great Songwriters – Harry Warren | |
| I Know Why | Glenn Miller & Paula Kelly & The Modernaires | Green Eyes | |
| I Know Why and So Do You | Falconaires - US Air Force Band of the Rockies | String of Pearls - A Tribute to Major Glenn Miller | |
| I Don't Know Why (I Just Do) | Benny Goodman and His Orchestra | Benny Goodman 1931-1935 (feat. Billie Holiday, Glenn Miller, Jack Teagarden, Joe Sullivan, Gene Krupa, Coleman Hawkins, Benny Carter) | |
| I Know Why | Glenn Miller | Sun Valley Serenade | |
| I Know Why | Glenn Miller | Sunset Serenade Broadcast November 22, 1941 (Live) | |
| I Know Why | Members of the Glenn Miller Orchestra | The Big Band Era , Volume 8 - The Passing Of An Era | |
| I Know Why | Glenn Miller and His Orchestra | Greatest Hits Volume 5 (1941 - 1942) | |
| I Know Why | Glenn Miller | We're Still In Love | |
| I Know Why and So Do You | Glenn Miller and His Orchestra | Remember Glenn | |
| I Know Why (And So Do You) | Glenn Miller Orchestra | 100 Vocal & Jazz Classics - Vol. 13 (1941-1942) | |
| I Know Why (And So Do You) | Glenn Miller | Moods, Vol. 3 | |
| I Know Why | Glenn Miller Orchestra | 16 Big Band Hits (Vol 8) | |
| I Know Why | Glenn Miller and His Orchestra | I Know Why - Single | |
| I Know Why | Glenn Miller | Hereafter (Remastered) | |
| I Know Why (Sun Valley Serenade) | Syd Lawrence & His Orchestra | Plays Glenn Miller | |
| Memories of Glenn Miller: American Patrol / Pennsylvania 65000 / At Last / Tuxedo Junction / I Know Why / Moonlight Serenade / In the Mood | Nigel Ogden | The Mighty Wurlitzer: 1940's | |
| I Know Why (And So Do You) | Glenn Miller | The Sessions, Vol. 3 | |
| I Know Why (And So Do You) | Glenn Miller | The Best Of (1938-1942) Vol 2 | |
| I Know Why | Glenn Miller Orchestra | The Passing of an Era (Vol 8) | |
| I Know Why | Ray McKinley | The New Glenn Miller Orchestra | |
| I Know Why | Glenn Miller | Glenn Miller Greatest Hits | |
| I Know Why | Glenn Miller | Glenn Miller's All Time Biggest Hits | |
| I Know Why | Glenn Miller | Glenn Miller Anthology, Vol. 3 (That Old Black Magic) | |
| I Know Why | Glenn Miller | Above & Beyond - Glenn Miller Vol. 2 | |
