the brassword cd "congress of vienna" has it. so does one of the bangers and mash cds. i think brassworks is on itunes.

You can purchase a CD of it from Frank Davis, the Brassworks trumpet player.

The dance was created By John Hertz from some Scandinavian folk records. I had a friend of mine check the copyright clearance who worked for the library of congress. As John combined elements from several recording into a new work. The new work belongs to John. However as the lead sheets were written by other such as Frank and no one has made any claims in the 20 or so years this has been used at Gaskells, it is probably considered an "undocumented folk song." Just be sure to credit John and Frank when you use it.

Anyway here is the leadsheet in abc music notation. You can learn more about this musical notation and how to convert to midi from this wicki site:

en.wikipedia.org/wiki/ABC_..._notation)

X: 1
T: Congress of Vienna
M: 3/4
L: 1/8
K:C
e2|"Am"(c2 A2) e2|"Em/G"(B2 G2) e2|"F"(A2 F2) e2|"E"E4 e2 \
P:A
|:"Am"(c2 A2) e2|"Am/G"(c2 A2) e2|
|"Em"(d2 B2 G2|"E/D"E4) (^F^G|"Am/C"A2 ^G2 A2|"G/D" {c}B2 {cB}A2 B2)|"Am/E"(c>d cB c2|"F"A6)|
|"D"(({g}^f)e f^gaf|"Am"edef e2)|("Dm/F"dc defd|"Am/E"cBcd c2)|("G"B/2c/2B/2A/2 Bc"Em"dB |
|1 "Am"A4) e2:|2 "Am"A4) (GA \
P:B
|:"G"B2 ^c2 d2)|"Bm/D"(^fe d^c B2)|"D/F#"(a2 ^f2 d2)|"Bm/E"(^fe) (d^c) B2|
|"G"(B2 ^c2 d2)|"Bm/D"(^fe d^c B2)|"G/B"(ba"C#dim"ga"D"^fd|1 "A/E"e4) (GA:|2 "Em"e6) \
P:C
|:"Em/A"(e3 d ^cB)|
|"Am"A>A A2 A2|c>c "Em"B>B E2|((3BcB) "Am"A2 A2|"Em/A"(e3 d ^cB)|"Am"A>A A2 A2|c>c "Em"B>B G>G|
|"Am"A2 A2 z2 \
P:D
::z2 z2 e2|"A"(e2 ^c2) c2|(^c2 e2 g2)|("D"(3g^fe f2 d2)|"D"(d2 ^f2 a2)|
|"A7"(a3 g e2)|(^c2 e2 g2)|"D"({a}(3gfe f2 d2)|"A"e2 e2 z2 \
P:E
:|z6|"Em/A"(e3 d ^cB)|"Am"A>A A2 A2|
|c>c "Em"B>B G2|((3BcB) "Am"A2 A2|"Em/A"(e3 d ^cB)|"Am"A>A A2 A2|c>c "Em"B>B G>G|"Am"A2 A2 z2|z2 z2 e2|]

both the brassworks album, congress of vienna, and the bangers & mash album, breakfast at fezziwig's have the music.
the earliest recording that i've heard of if is available at tibit.com/congress/

there is video on youtube at www.youtube.com/watch
if the link fails look for it by name.

I have a booklet with john hertz's instructions, you can borow it next time you're over.

www.fridaynightwaltz.com/cov.html has the steps.