(There's no video for iTunes 10.6.3 yet. Please contribute to MR and add a video now!)
iTunes 10.6.3 is the last version to support Mac OS X 10.5.8 Leopard.
See also: iTunes 9.2.1 (the last version to support Mac OS X 10.4 Tiger).
iTunes10-6-3.dmg (170.27 MiB / 178.55 MB)
iTunes v10.6.3 (last to support Leopard) / DMG image
Mac OS X 10.5.8 and up
Emulating this? It should run fine under: QEMU