"Sakura, Sakura" (sakura is repeated in the common title) is said to be koyoo ("an old song"); it's traditional, but not a folk song in the strict sense of the word. Lyrics & translation of are HERE (midi is not recommendable); pronunciaton guide (not an orthographical transcription), free translation, and sheet music are HERE; lyrics & unpoetic translation, with a good arranged midi, are HERE; and a less common version (lyrics, translation, & a good koto- & shakuhachi-sounding midi) is HERE.