Here's ABC for The Butterfly, copied from Henrik Norbert's ABC Page :

X:1
T:Butterfly, The
R:slip jig
C:Tommy Potts
D:Bothy Band: 1975.
Z:id:hn-slipjig-3
M:9/8
K:Edor
B2E G2E F3|B2E G2E FED|B2E G2E FGA|B2d d2B AFA:|
|:B2d e2f g3|B2d g2e dBA|B2d e2f g2a|b2a g2e dBA:|
|:B3 B2A G2A|B3 BAB dBA|B3 B2A G2A|B2d g2e dBA:|

If you don't know about ABC, take the link above and also this one:The ABC Homepage. You can find software for turning it into sheet music such as ABC2Win and Muse. Also do a search of the forum, we've discussed it pretty thoroughly lately.