I've sent the MIDI of Carusi's tune to Joe for posting here. I forgot to slow down the tempo from MIDI's default of 120, so if you like it, slow it down yourself.
The spelling Carisi is a mistake. It's Carusi, and the music was published in Louisville KY in 1840, according to the Lester Levy site. It was for guitar and is in 3/4 time.
It's in the key of A, but in the second part he adds chromatic notes. At first they are D#'s, but then he puts in an F natural. I don't like the F natural myself, and I believe that if I played the song, I would omit it. It may have been a fad of the time.
If you don't read music and are sounding out the chords, then I would try a B when a D# arrives.
Click to play (joeweb)